Devices and methods for treatment of obesity

ABSTRACT

Methods, devices, tools and assemblies for treating a patient to effect weight loss. One method embodiment involves passing a device including an expandable member in a collapsed configuration and a buoyancy member through an opening in the skin of a patient and into the abdominal cavity of the patient, and anchoring at least a portion of the expandable member, relative to at least one structure in the abdominal cavity. Devices including at least one expandable member and at least one buoyancy member are provided.

CROSS-REFERENCE

This application is a continuation-in-part application of co-pendingapplication Ser. No. 11/407,701, filed Apr. 19, 2006, which is herebyincorporated herein by reference thereto, in its entirety, and to whichapplication we claim priority under 35 USC §120.

This application claims the benefit of U.S. Provisional Application No.60/833,284, filed Jul. 24, 2006, and U.S. Provisional Application No.60/877,595, filed Dec. 28, 2006, both of which applications are herebyincorporated herein, in their entireties, by reference thereto.

This application also hereby incorporates herein by reference thereto,in its entirety, co-pending application Ser. No. (application Ser. No.not yet assigned, Attorney's Docket No. EXPL-001CIP2) filed on even dateherewith, and titled “Devices and Methods for Treatment of Obesity”.

FIELD OF THE INVENTION

The present invention relates to treatment of obesity, more particularlyto implantable devices and methods of implanting the devices in theabdominal cavity to treat an obese patient.

BACKGROUND OF THE INVENTION

Obesity has become a major health concern, both nationally andinternationally. The National Center for Health Statistics (NCHS)estimates that over 120 million Americans are overweight, includingabout 56% of the adult population. Of these, about 52 million areconsidered obese, as measured by a body mass index (BMI) of 30 orgreater. In Europe, an estimated 77 million people are obese, asmeasured by the same standard. This problem is not limited to westernnations, as many developing countries are reported to have obesity ratesover 75% of the adult population.

Co-morbidities that are associated with obesity include, but are notlimited to type II Diabetes, high blood pressure, sleep apnea, strokeand arthritis, the symptoms of which often tend to be lessened oralleviated upon loss of weight by a person so affected.

In the U.S., options for treatment of obesity are currently quitelimited. Current treatment methodologies typically rely upon surgicallyintroducing a “malabsorptive” environment in the gastro-intestinaltract, a restrictive environment, or a combination of these. Oneavailable treatment method is gastric bypass surgery and another isreferred to as gastric banding (one of these techniques is referred toas the LAPBAND™ procedure). These procedures are limited to only thosepatients with a BMI over 40 (or over 35, with co-morbidities present).

Gastric bypass procedures incur a great deal of morbidity and create amalabsorptive state in the patient by passing a large portion of theintestines. Serious side effects, such as liver failure have beenassociated with this procedure, as well as chronic diarrhea. Anothersurgical procedure that has a high degree of morbidity associated withit is known as the “Gastric Bypass Roux-en-Y” procedure. This procedurereduces the capacity of the stomach by creating a smaller stomach pouch.The small space holds only about one ounce of fluid. A tiny stomachoutlet is also surgically created to slow the speed at which food leavesthe stomach. Staples are used to create a small (15 to 20 cc) stomachpouch, with the rest of the stomach being stapled completely shut anddivided from the stomach pouch. The small intestine is divided justbeyond the duodenum, brought up, and connected to the newly formedstomach pouch. In addition to the considerable morbidity associated withthis procedure, other disadvantages include “dumping syndrome”, wherestomach contents are literally “dumped” rapidly into the small intestinewhich may lead to nausea, weakness, sweating, faintness, and diarrhea;hernias resulting from the surgery; gallstones; leakage of theconnection between the pouch and the intestine; stretching of the pouchthat was formed; nutritional deficiencies; and possible dehiscence ofthe staples.

The LAPBAND™ is a band that, when placed, encircles the fundus-cardiajunction and is inflatable to constrict the same. It does not reduce thevolume of the stomach, but rather restricts passage of food into thestomach, the theory being that the patient will feel satiety with a muchsmaller volume of food than previously. Although the LAPBAND™ procedureis less invasive than a gastric bypass procedure, it also typicallyachieves less weight loss. Further, it is not a simple procedure andrequires a substantial amount of training by a surgeon to becomeproficient in performing the procedure. Also, a substantial amount ofdissecting and suturing is required because the pathway by which theband is introduced is not an existing pathway, and must be establishedby dissection. Great care is required to avoid blood vessels and nervesthat may be in the intended pathway to be created by the dissection.After placing the band around the fundus-cardia junction, the ends ofthe band must be connected together and then it must be cinched downinto place. Additionally, complications such as erosion at thefundus-cardia junction, slippage of the band from its intended location,nausea/vomiting, gastroesophageal reflux, dysphagia and lack ofeffectiveness in causing weight loss have been reported.

Intragastric balloons have also been placed, in an attempt to fill aportion of the volume in the stomach, with the theory being that it willthen require less food than previously, to give the patient a sensationof fullness or satiety. This procedure involves delivery of a balloon(typically, transorally) to the interior of the stomach and inflation ofthe balloon to take up a portion of the volume inside the stomach.However, intragastric balloons may also lead to complications such asobstruction, vomiting and/or mucosal erosion of the inner lining of thestomach. The balloon can break down over extended exposure to thestomach's acids, and in some cases, after breaking down, the balloontranslated through the intestines and caused a bowel obstruction.

Gastrointestinal sleeves have been implanted to line the stomach and/ora portion of the small intestines to reduce the absorptive capabilitiesof the small intestine and/or to reduce the volume in the stomach, byreducing the available volume to the tubular structure of the graftrunning therethrough. Although weight loss may be effective while thesetypes of devices are properly functioning, there are complications withanchoring the device within the stomach/GI tract, as the stomach and GItract function to break down things that enter into them and tomove/transport them through. Accordingly, the integrity of the anchoringof the device, as well as the device itself may be compromised over timeby the acids and actions of the stomach and GI tract.

A sleeve gastrectomy is an operation in which the left side of thestomach is surgically removed. This results in a much reduced stomachwhich is substantially tubular and may take on the shape of a banana.This procedure is associated with a high degree of morbidity, as a largeportion of the stomach is surgically removed. Additionally, there arerisks of complications such as dehiscence of the staple line where thestaples are installed to close the surgical incisions where the portionof the stomach was removed. Further, the procedure is not reversible.

In the laparoscopic duodenal switch, the size of the stomach is reducedin similar manner to that performed in a sleeve gastrectomy.Additionally, approximately half of the small intestine is bypassed andthe stomach is reconnected to the shortened small intestine. Thisprocedure suffers from the same complications as the sleeve gastrectomy,and even greater morbidity is associated with this procedure due to theadditional intestinal bypass that needs to be performed. Still further,complications associated with malabsorption may also present themselves.

An inflatable gastric device is disclosed in U.S. Pat. No. 4,246,893, inwhich a balloon is inserted anteriorly of the stomach and posteriorly ofthe left lobe of the liver. The balloon is then inflated to compress thestomach so that it fills with less food that would ordinarily bepossible. Not only does this device compress the stomach, but it alsocompresses the liver, as seen in FIG. 5 of the patent, which may causecomplications with the liver function. Additionally, the balloon issimply placed into this location, and there is no assurance that it willnot migrate and lose its effectiveness in compressing the stomach to thedegree intended. Still further, the balloon is of a simple sphericaldesign, and, as such, extends pressure outwardly in all directions, 360degrees, in all planes. Accordingly, the liver is compressed just asmuch as the stomach is. Also, the compression forces against the stomachare not ideal, as the spherical balloon conformation does not match theconformation of the expanding stomach. The stomach is not spherical whenexpanded, or concave with a constant radius of curvature, but expandsinto a designated space that allows the fundus to expand preferentiallymore than other parts of the stomach.

Brazzini et al. in WO2005/18417 discloses at least two or moreexpandable devices used to treat obesity, in which the devices areinserted through the abdominal wall and anchored against the externalsurface of the stomach wall by an anchoring mechanism that extendsthrough the stomach wall and fixes to the internal surface of thestomach wall.

U.S. Patent Publication No. 2005/0261712 to Balbierz et al. describescapturing a device against the outer surface of the stomach wall to forma restriction that appears to function similarly to the restrictionimposed by the LAPBAND™. The anchoring of the devices disclosed reliesupon placement of features against the internal wall of the stomach toform an interlock with the device which is placed against the externalwall of the stomach.

U.S. Patent Publication Nos. 2005/0267533 and 2006/0212053 to Gertnerdisclose devices for treatment of obesity that use one or more anchoringmechanisms that are passed through the wall of the stomach to establishan anchor.

U.S. Pat. No. 6,981,978 to Gannoe discloses devices for reducing theinternal cavity of the stomach to a much smaller volume, which may beused to carry out a bypass procedure. Stapling is employed to isolatethe smaller volume in the stomach, and thus the same potentialdisadvantages are present as with other stapling procedures describedherein.

U.S. Pat. No. 6,186,149 to Pacella et al. describes an occluder devicethat can be used as a dietary control device (see FIG. 8C). The occluderdevice is placed against the wall of the stomach and inflated to pressinwardly on the stomach wall. A frame is wrapped around the stomach walland is inflated to press against the stomach wall. However, there is nodisclosure of how the frame might be adjusted to maintain a positionrelative to the stomach wall as the size of the stomach varies.

Gastric reduction techniques have been attempted, such as by insertinginstruments trans-orally and reducing the volume of the stomach bystapling portions of it together. However, this technique is prone tofailure due to the staples pulling through the tissues that they aremeant to bind.

Techniques referred to as gastric pacing endeavor to use electricalstimulation to simulate the normal feedback mechanisms of a patient thatsignal the brain that the patient is full, or satiated. While thesetechniques are less invasive than some of the other existing treatments,statistics to date have shown that the amount of weight lost by usingsuch techniques is less than satisfactory.

Currently marketed drugs for weight loss, such as XENICAL®, MERIDIA® andPhen fen have largely failed, due to unacceptable side effects andcomplications, and sometimes to an ineffective amount of weight loss.Other drugs that are on the horizon include ACCOMPLIA® and SYMLIN®, butthese are, as yet, unproven.

The risk and invasiveness factors of currently available surgeries areoften too great for a patient to accept to undergo surgical treatmentfor his/her obesity. Accordingly, there is a need for less invasive, yeteffective surgical treatment procedures for morbidly obese patients(patients having a BMI of 35 or greater). Also, since the currentsurgical procedures are currently indicated only for those patientshaving a BMI of 40 or greater, or 35 or greater when co-morbidities arepresent, it would be desirable to provide a surgical procedure thatwould be available for slightly less obese patients, e.g., patientshaving a BMI of 30 to 35 who are not indicated for the currentlyavailable surgical procedures. It would further be desirable to providea surgical procedure that would be indicated for obese patients having aBMI in the range of 30-35, as well as for more obese patients.

SUMMARY OF THE INVENTION

The present invention provides methods, devices, tools and assembliesfor treating a patient to assist with weight loss. One method embodimentinvolves passing a device including an expandable member in a collapsedconfiguration and a buoyancy member into the abdominal cavity of thepatient, and anchoring at least a portion of the expandable member,relative to at least one structure in the abdominal cavity.

A method of treating a patient is provided that includes the steps ofpassing a device into the abdominal cavity of the patient, wherein thedevice includes at least one attachment member extending from a mainbody portion thereof; positioning an inferior portion of the device inthe abdominal cavity; and anchoring that at least one attachment memberto an inner surface of the abdominal wall.

A method of treating a patient is provided that includes steps of:passing a guide rail into the abdominal cavity of the patient; passingan anchoring frame, guided by the guide rail, into the abdominal cavity;anchoring the anchoring frame to at least one structure in the abdominalcavity; passing a device, guided by the guide rail, into the abdominalcavity; and attaching the device to the anchoring frame.

A method of treating a patient is provided that includes steps of:passing a guide rail into the abdominal cavity of the patient, whereinthe guide rail is selected from one of: at least one guidewire; at leastone flexible wire facilitating viewing out of a distal end portionthereof from a proximal end portion thereof; at least one rod; or aflexible steerable catheter; passing an anchoring frame, guided by theguide rail, into the abdominal cavity; anchoring the anchoring frame toat least one structure in the abdominal cavity; passing a device, guidedby the guide rail, into the abdominal cavity; and attaching the deviceto the anchoring frame.

A method of treating a patient is provided, including steps of: passingan anchoring frame into the abdominal cavity of the patient; deliveringanchoring members, attached to the anchoring frame, through at least onestructure in the abdominal cavity that the anchoring frame is to beanchored to, through the skin and out of the patient; fixing theanchoring members externally of the abdominal cavity to anchor theanchoring frame to the at least one structure in the abdominal cavity;passing a device, into the abdominal cavity; and attaching the device tothe anchoring frame.

A method of treating a patient is provided, including steps of: passinga buoyancy member into the abdominal cavity of the patient; anchoringthe buoyancy member to at least one structure in the abdominal cavity;passing a device into the abdominal cavity; and attaching the device tothe buoyancy member.

A method of treating a patient is provided, including steps of: passinga device including an expandable member having at least onetrans-abdominally detectable marker; advancing the device into theabdominal cavity of the patient while tracking and guiding the advancingby trans-abdominally detecting the location of the at least one marker,relative to the patient's anatomy, as the device is advanced; andanchoring at least a portion of the expandable member, relative to atleast one structure in the abdominal cavity.

A method of monitoring functionality of a device implanted in theabdominal cavity of a patient to enhance weight loss is provided,including: providing a handheld monitoring device outside of thepatient; and wirelessly communicating with at least one sensor on thedevice located in the abdominal cavity.

A method of treating a patient is provided, including: providing adevice implanted in the abdominal cavity of the patient, wherein thedevice occupies a space in the abdominal cavity to perform at least oneof: prevention of expansion of the stomach of the patient into the spaceand compression of a portion of the stomach; wherein the device includesat least one electrode on a surface thereof in contact with the stomachof the patient, said at least one electrode being electrically connectedto a stimulation signal controller; and delivering a stimulation signalfrom the controller to the at least one electrode to stimulate at leastone contraction of at least one muscle in the stomach.

A method of treating a patient is provided, including: passing a deviceinto the abdominal cavity of the patient; anchoring at least a portionof the device, relative to at least one structure in the abdominalcavity; and occupying a space in the abdominal cavity with the device tosubstantially restrict expansion of the fundus of the stomach, andrestraining the stomach to a shape resembling a tube, but wherein atleast a portion of the antrum is left unrestrained.

A method of treating a patient is provided, including: passing a deviceinto the abdominal cavity of the patient; anchoring at least a portionof the device, relative to at least one structure in the abdominalcavity; and occupying a space in the abdominal cavity with the device tosubstantially restrict expansion of the fundus of the stomach, andrestraining the stomach to a shape resembling a tube, but wherein asmall pouch is left unrestrained at a superior end portion of thestomach.

An implantable device for treatment of a patient to assist weight lossis provided, wherein the device includes: an expandable memberconfigured to be positioned in an abdominal cavity of the patient, theexpandable member configured to be expanded from a contractedconfiguration to an expanded configuration after placement of the devicein the abdominal cavity, and to substantially maintain a size and shapeof the expanded configuration. The expandable member, in the expandedconfiguration, has a buoyancy characteristic relative to its surroundingwhen implanted in the abdominal cavity. The device further includes abuoyancy member having a buoyancy characteristic different from thebuoyancy characteristic of the expandable member, to alter a combinedbuoyancy characteristic of the device.

A method of making an implantable device for treatment of a patient toassist weight loss is provided, wherein the device includes anexpandable member configured to be positioned in an abdominal cavity ofthe patient, the expandable member configured to be expanded from acontracted configuration to an expanded configuration after placement ofthe device in the abdominal cavity, and to substantially maintain a sizeand shape of the expanded configuration, and a buoyancy member fixed tothe expandable member and contained within an internal cavity of theexpandable member. The method of making includes: providing a moldhaving a shape of the buoyancy member integral with a shape of theexpandable member; molding a wall of polymeric material over the mold;removing the molded wall of material from the mold; inverting a moldedbuoyancy member portion of the wall into an internal cavity defined by amolded expandable member portion of the wall; and sealing a slitremaining from the inverting.

An anchoring frame deployment tool is provided that includes: a recessor cavity formed in a distal portion shaped and dimensioned to receivean anchoring frame therein; needles and a driving mechanism for drivingthe needles through the distal portion and the anchoring frame; whereinthe needles have sufficient length to extend through an abdominal wallof a patient and out through the skin of the patient when the anchoringframe is contacted to an inner wall surface of the abdominal wall.

An anchoring frame for anchoring a device to an internal structure in apatient's body is provided, including: a plurality of beams linked to becompressed into a narrow configuration and expanded to an expandedconfiguration; and a mechanical linking feature on each of at least twoof the beams, the mechanical linking features configured to mechanicallyengage with mating features on the device.

An assembly of mating engagement members for engaging anintra-abdominal, extra-gastric implant device with an anchoring frame isprovided, wherein the assembly includes: a rail having a series oftransversely placed openings along a length thereof; a channelconfigured to receive the rail and having at least one detent configuredto pass through a wall of the rail through one of the openings; and anactuator for preventing the at least one detent from passing through thewall when in a first configuration; and allowing passage of the at leastone detent through the wall when in a second configuration.

These and other features of the invention will become apparent to thosepersons skilled in the art upon reading the details of the methods,devices, tools and assemblies as more fully described below.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates the anatomy of the abdominal cavity and its contents,and surrounding features.

FIG. 2A is an illustration of a diaphragm in an isolated view,illustrating the conformation of the diaphragm as it exists in the body.

FIG. 2B illustrates the diaphragm in position relative to the rib cage.

FIGS. 3A and 3B show views of a main body of a device with a shape andsize approximating the shape and size of a full (post-prandial) stomach.

FIG. 4 illustrates (by arrows) potential locations on the stomach wallthat can be displaced or compressed by one or more expandable devices asdescribed herein.

FIG. 5A shows an embodiment of a device having a buoyancy membercontained in an internal chamber of an expandable member.

FIGS. 5B-5C schematically illustrate alternative embodiments of buoyancymembers.

FIGS. 6A-6C illustrate a nested chamber configuration of a buoyancymember.

FIG. 7 illustrates an embodiment of a device that includes a buoyancymember within an expandable member, where the buoyancy member is formedin the shape of an elongated spine.

FIG. 8 illustrates an arrangement in which a self-expanding buoyancymember is provided within an expandable member of the device.

FIG. 9 illustrates another arrangement of a device including aself-expanding buoyancy member.

FIG. 10 shows a device having a buoyancy member that has inner and outerchambers.

FIGS. 11A-11B illustrate devices that include a substantially rigidbuoyancy member.

FIG. 11C shows a buoyancy member having a substantially cylindricalshape.

FIG. 11D illustrates a plurality of the shapes shown in FIG. 11C, joinedby links to form a buoyancy member.

FIGS. 12A-12B illustrate another example of a buoyancy member.

FIG. 13 illustrates another arrangement of a buoyancy member within anexpandable member of a device.

FIG. 14 illustrates another arrangement of a buoyancy member within anexpandable member of a device.

FIG. 15 illustrates a device wherein a buoyancy member forms an internalspine in an expandable member.

FIG. 16A illustrates an embodiment of a buoyancy member that is made offoam.

FIG. 16B is a cross-sectional view of the buoyancy member of FIG. 16Ataken along line 16B-16B.

FIG. 16C is a cross-sectional illustration of an alternative embodimentof a foam buoyancy member.

FIG. 16D is a cross-sectional illustration of the buoyancy member ofFIG. 16C, after closing the internal chamber.

FIG. 16E is a cross-sectional illustration of the buoyancy member ofFIG. 16 b, after closing the internal chamber.

FIG. 17 illustrates a mandrel that is shaped to conform to the openingin the buoyancy member shown in FIG. 16A.

FIG. 18A-18K illustrate alternative configurations for formingstructural type buoyancy members.

FIGS. 19A-19B illustrate two different examples of molded buoyancymembers that can be used as an internal spine.

FIG. 20 illustrates a buoyancy member fixed to an inner surface of anexpandable member.

FIG. 21 shows an alternative embodiment of buoyancy member that ismolded from foam.

FIG. 22 illustrates an embodiment of a device having a buoyancy memberattached to an inner wall surface of an expandable member to form aninternal, buoyant spine.

FIG. 23 illustrates a device having an elongated positioning loopattached thereto.

FIG. 24 illustrates an exploded view of reinforcement tab and loopstructures, demonstrating one method of bonding these structures to anexpandable member.

FIG. 25A illustrates a positioning tab bonded to a portion of an outersurface of an expandable member.

FIG. 25B is a cross sectional view of FIG. 25A taken along line 25B-25B.

FIG. 25C shows a positioning tab that lies substantially flush with asurface of an expandable member.

FIGS. 26A-26B illustrate an embodiment where tab(s) is/are extended toprovide a shell-like rigidifying support of an expandable member.

FIG. 26C illustrates a configuration where a reinforced frame structureor reinforcement backing layer extends superiorly of tabs.

FIG. 27 shows an inferior portion of a device to illustrate analternative arrangement for fixing or anchoring tab(s) to an internalabdominal structure.

FIG. 28 schematically illustrates one suture having been tied down toanchor a portion of a tab to the inner surface of the abdominal wall.

FIG. 29 shows a mold that is three dimensionally shaped to form anexpandable member and a buoyancy member integrally as a single moldedproduct.

FIG. 30A illustrates the molded product after removing it from the moldshown in FIG. 29.

FIG. 30B shows the molded product of FIG. 30A pushing on the portion ofthe product that will form buoyancy member to invert it.

FIG. 30C illustrates an open channel or slot after inverting thebuoyancy member portion as shown in FIG. 30B.

FIG. 31 illustrates an alternative mold in which a buoyancy portion isformed to extend superiorly of the superior portion of expandable memberportion.

FIGS. 32A-32E illustrate steps that may be carried out during aprocedure for implanting an expandable extra-gastric device according toan embodiment of the present invention.

FIG. 33F illustrates a sectional view of a patient (viewed from the feetof the patient) that shows the anchoring of an anchoring frame to theabdominal wall.

FIG. 33G is a schematic illustration from a frontal view perspective,showing an anchoring frame anchored in place against the anteriorabdominal wall.

FIG. 33H illustrates advancement of a device, using a device deploymenttool having already been preloaded with the device in a collapsed orcompressed configuration over a guidewire.

FIG. 33I shows a sectional illustration of a device having been lockedinto position on an anchoring frame.

FIG. 33J shows trimming of conduit(s) to an appropriate length forconnection with an adjustment member.

FIG. 33K shows an adjustment member being anchored subcutaneously, tothe external surface of the abdominal wall.

FIG. 34 illustrates restriction of the stomach from expanding to itspost-prandial, expanded configuration.

FIGS. 35A-35D illustrate and instrument and method for anchoring ananchoring frame to an internal abdominal structure.

FIG. 35E illustrates a patient's skin with needles protrudingtherethrough.

FIG. 35F illustrates sutures extending from openings through the skin ofthe patient after removal of the needles shown in FIG. 35E.

FIG. 35G illustrates one embodiment of a suture lock or clip installedover a suture.

FIG. 35H illustrates a distal end portion or working end of a knotpusher tool being used to lock down a clip over a suture.

FIG. 35I illustrates another embodiment of a knot pusher tool.

FIG. 36A illustrates an alternative arrangement of needle and anchoringmember that can be used for anchoring an anchoring frame.

FIG. 36B illustrates an embodiment of a speed nut.

FIG. 36C illustrates a plurality of ribbons having been anchored byfixing speed nuts against the external surface of the abdominalwall/fascia.

FIGS. 36D-36E illustrate another embodiment of a speed nut that isconfigured to assume undeployed (or extended) and deployed (orcompressed) configurations or states.

FIGS. 36F-36G show side and perspective views of another embodiment ofspeed nut.

FIG. 36H illustrates a ribbon having barbs, with barbs catching againstthe abdominal wall/fascia, thereby piercing into the abdominalwall/fascia and flaring out radially somewhat.

FIGS. 37A-37B illustrate an expandable anchoring frame.

FIGS. 37C and 37D illustrate longitudinal sectional views of a portionof an arm or beam and ingrowth sheet, where FIG. 37C shows a needle in aretracted configuration, and FIG. 37D shows the needle protrudingthrough the arm or beam and ingrowth sheet.

FIGS. 38A-38B illustrate mating engagement members that can be providedas part of any of the frames described herein and any of the expandablemembers described herein, respectively.

FIG. 38C illustrates an expandable member in a compacted, low profileconfiguration for insertion into the abdominal cavity of a patient, withthe central lumen of a rail having been threaded over a guidewire forsliding delivery and guidance of the device into the abdominal cavity.

FIGS. 39A-39C illustrate another embodiment of mating engagementmembers.

FIGS. 40A-40H illustrate various embodiments of buoyancy members thatalso function as anchoring frames.

FIG. 41 shows examples of implant markers and sensors that may beincluded on a device.

FIG. 42 illustrates a procedural step for anchoring an anchoring frameto an internal surface of an abdominal wall using ribbons.

FIG. 43 illustrates a handheld device configured to communicate with oneor more sensors located internally of a patient.

FIG. 44 illustrates an example where a surface of an expandable memberis provided with sensors comprising electrodes that can be used todeliver pacing signals to the stomach.

FIG. 45 illustrates another embodiment of a device 10 configured to pacethe stomach.

DETAILED DESCRIPTION OF THE INVENTION

Before the present devices methods and instruments are described, it isto be understood that this invention is not limited to particularembodiments described, as such may, of course, vary. It is also to beunderstood that the terminology used herein is for the purpose ofdescribing particular embodiments only, and is not intended to belimiting, since the scope of the present invention will be limited onlyby the appended claims.

Where a range of values is provided, it is understood that eachintervening value, to the tenth of the unit of the lower limit unlessthe context clearly dictates otherwise, between the upper and lowerlimits of that range is also specifically disclosed. Each smaller rangebetween any stated value or intervening value in a stated range and anyother stated or intervening value in that stated range is encompassedwithin the invention. The upper and lower limits of these smaller rangesmay independently be included or excluded in the range, and each rangewhere either, neither or both limits are included in the smaller rangesis also encompassed within the invention, subject to any specificallyexcluded limit in the stated range. Where the stated range includes oneor both of the limits, ranges excluding either or both of those includedlimits are also included in the invention.

Unless defined otherwise, all technical and scientific terms used hereinhave the same meaning as commonly understood by one of ordinary skill inthe art to which this invention belongs. Although any methods andmaterials similar or equivalent to those described herein can be used inthe practice or testing of the present invention, the preferred methodsand materials are now described. All publications mentioned herein areincorporated herein by reference to disclose and describe the methodsand/or materials in connection with which the publications are cited.

It must be noted that as used herein and in the appended claims, thesingular forms “a”, “an”, and “the” include plural referents unless thecontext clearly dictates otherwise. Thus, for example, reference to “aconduit” includes a plurality of such conduits and reference to “theexpandable member” includes reference to one or more expandable membersand equivalents thereof known to those skilled in the art, and so forth.

The publications discussed herein are provided solely for theirdisclosure prior to the filing date of the present application. Nothingherein is to be construed as an admission that the present invention isnot entitled to antedate such publication by virtue of prior invention.Further, the dates of publication provided may be different from theactual publication dates which may need to be independently confirmed.

Definitions

A “compliant” material refers to a material that is stretchable orexpandable. This expansibility allows the material to increase indimension substantially more than a noncompliant or semi-compliantmaterial, prior to failure. For example, when formed as a balloonstructure, a compliant material comprises an expansibility property ofbeing able to increase its radius, beyond its formed radius, underpressure applied into the balloon, by 100 percent or more, withoutrupturing.

A “noncompliant” material refers to a material that, when formed as aballoon structure, can increase its radius beyond its formed radius,under pressure applied into the balloon, only up to about 10 percent orless prior to rupturing.

A “semi-compliant” material refers to a material that, when formed as aballoon structure, can increase its radius beyond its formed radius,under pressure applied into the balloon, by an amount between about 10percent and about 100 percent, prior to rupturing.

The “wall” of the stomach refers to all of the layers that make up thestomach wall, including the mucosa, submucosa, muscular layers andserosa. A “layer”, “layer of the stomach wall” or “stomach wall layer”refers to a mucosal layer, submucosal layer, muscular layer or serosallayer.

A “proximal” end of an instrument is the end that is nearer the surgeonwhen the surgeon is using the instrument for its intended surgicalapplication.

A “distal” end of an instrument is the end that is further from thesurgeon when the surgeon is using the instrument for its intendedsurgical application.

An “internal body structure” when referred to as a structure to which adevice is to be anchored, refers to a structure internal to the skin ofa patient, and which can be within the abdominal cavity of the patient,or just outside of it, such as including the outer surface of a wallthat partially defines the abdominal cavity. Structures to which adevice can be anchored include, but are not limited to: one or moreribs, the intercostal muscles, the abdominal surface of the diaphragm,the stomach (but where the anchor does not pass through the wall of thestomach), the anterior abdominal wall, the posterior abdominal wall andthe lateral abdominal wall, the esophagus, the angle of his in thestomach, the gastro-intestinal junction, the gastro-esophageal junction,the columnar ligaments of the diaphragm near the gastro-esophagealjunction, the superior aspect of the omentum, peritoneum, liver,connective tissues, ligaments, and blood vessels.

An “internal abdominal structure” refers to an internal body structurethat is within the abdominal cavity of the patient, including theabdominal wall. For example, attachment to an inner wall surface of theabdominal wall is an attachment to an internal abdominal structure.

The preferred embodiments of the present invention prevent the possibleissue of erosion caused by an expandable member, by not requiringanchoring to the stomach, and further, by not requiring a substantialcompression force to be applied when the stomach is not full of food. Byallowing the stomach to move freely in the constrained spaced providedby the expandable member, the stomach's possible expansion size will bedecreased, but there will be less opportunity for the formation ofpressure necrosis since no one region will be subjected to concentratedforces. With the device in place, there is substantially nodistensibility of the stomach as normal exists with an unconstrainedstomach. With distensibility restricted and gastric volume reduced, asthe patient ingests food, the intra-gastric pressure will rise to alevel sufficient to produce satiety without distension or volumeexpansion of one or more regions of the stomach. The device occupies somuch volume in the abdominal cavity that the stomach does notsubstantially depart from the shape set by the device even when filledwith food. Another physiological benefit of the device is that thestomach's ability to relax in response to ingestion of food is reducedor eliminated, through producing earlier satiety. One additionalphysiological benefit of the expandable member may further be tosubstantially reduce the actual volume of the stomach itself, remodelingthe organ as the muscle contracts into its new shape over the period ofweeks or months (just as the heart remodels when constrained fromover-expansion). Remodeling the stomach allows the expandable member tobe implanted temporarily. The preferred embodiments also are positionedin a location to substantially fill the space normally occupied by thefundus, thus moving the stomach medially and wedging the stomach betweenthe expandable member and the medial and anterior aspects of the liver,and the spine posteriorly. This position also ensures that theexpandable member is almost entirely maintained underneath thediaphragmatic umbrella beneath the ribs on the left side, thusconcealing the expandable member, and preventing it from producing anunsatisfactory cosmetic result. Further, the preferred embodiments canhave elements for anchoring on one or more locations along the abdominalcavity wall to prevent migration. Further, the preferred embodiments areprovided with an outer surface that is very atraumatic. Embodimentsdescribed may include at least one expandable member, preferably aninflatable member, made of a material or material composite that isimpermeable to fluid, which may be substantially impermeable to gas andis at least impermeable to liquid, as well as embodiments having atleast two expandable members, with one expandable member being inflatedwith a gas and another expandable member being inflated with a liquid.Other embodiments include an expandable member and a buoyancy memberthat may or may not be expandable, and which adds buoyancy to thedevice. For example, a buoyancy member may be included with aliquid-filled expandable member of a device, that by itself, hasnegative buoyancy, so that the buoyancy member provides positivebuoyancy to bring the combined buoyancies of these components of thedevice nearer to a neutral buoyancy, when implanted into the abdominalcavity of a patient. It can be beneficial to make the combined buoyancyslightly positive in the abdominal cavity to help prevent the devicefrom migrating down in the patient.

The devices described herein can be provided as versatile devices. Forexample, the same device with an expandable member can be implanted andattached to either in a laparoscopic surgical procedure, an oraltrans-gastric procedure, or a variation of percutaneous procedures inwhich non general anesthesia and little or no insufflation are used. Thedevice can be implanted and anchored directly to at least one internalabdominal structure, or alternatively, can be implanted by fixing to ananchoring frame having been anchored to at least one internal abdominalstructure.

Abdominal Cavity Anatomy

FIG. 1 illustrates the anatomy of the abdominal cavity and its contents,and surrounding features. The abdominal cavity 100 is shown dividedamong four quadrants, the upper right quadrant 102, upper left quadrant104, lower left quadrant 106 and lower right quadrant 108, as divided bythe median axis 110 and transverse axis 112. The lower edge of theribcage is illustrated by the dotted line 114 and the diaphragm is shownat 116. As seen in FIGS. 2A and 2B, the diaphragm 116 is shaped like aparachute and sits within the ribs. The esophagus 118 passes through thediaphragm 116 and joins with the stomach 120. The left lobe 122 of theliver 121 lies anteriorly of the esophagus 118 and the fundus-cardiajunction 119. In one aspect of the invention, an expandable device isimplanted in an extra-gastric location (i.e., outside of the stomach)generally indicated at 124, and then expanded to occupy a space that thefundus of the stomach would ordinarily expand into when the stomach isfilled with food. The expanded device prevents this expansion by thefundus, thereby limiting the volume of the cavity in the stomach to amuch smaller volume than if the fundus had been allowed to expand intothe space. Alternatively, the device is expanded to apply pressure tothe fundus of the stomach in a downward direction (e.g., in a directiontoward the transverse axis 112 shown, with some transverse movementtoward the median axis 110 shown), and optionally, additionally to themain body of the stomach, to reduce the volume inside the stomach toeffect satiety in the patient with relatively less food ingested,relative to what the patient would require for satiety without theimplant in place.

Devices

At least some embodiments of devices described herein can be implantedpercutaneously, with a relatively quick and simple procedure thatrequires no general anesthesia and wherein only a single, small openingin a patient is required to deliver the device, which typically has asingle expandable member that is self anchoring or can be easilyanchored to maintain the simplicity and minimal invasiveness of theprocedure.

In other embodiments, configurations of expandable members are provided,where a device can contain one or more expandable members and one ormore steps of implantation and anchoring may be performedlaparoscopically with remaining steps being performed percutaneously.Further alternatively, implantation and anchoring a device may beperformed with most if not all steps being performed laparoscopically ororally through a trans-gastric procedure. Any of the devices describedherein can, of course, be implanted using open surgical procedures.Devices that can be implanted percutaneously can alternatively beimplanted using laparoscopic procedures.

Devices described herein can be implanted permanently, but are alsoconfigured for reversibility, to facilitate relatively simple removalprocedures, should it be desired to remove a device. Alternatively,devices according to the present invention can be implanted temporarily,such as over a period of months, and then removed or disabled whenfurther treatment is no longer required, or to allow an alternativetreatment to be applied.

Device Body Configurations

FIGS. 3A and 3B show views of a device 10 having a main body 10 m, 10 emwith a shape and size approximating the shape and size of the full(post-prandial) stomach 120. Although main body 10 m need not beexpandable/collapsible to perform restriction of stomach expansion, mainbody 10 m is typically formed from one or more expandable members 10 emas will be described in further detail below, for better performance ofintended functions and to allow less invasive procedures for implantingthe same.

Main body 10 m,10 em includes curved left and right sides 10 l and 10 r,respectively (FIG. 3A shows the posterior surface of main body 10 m,10em), wherein the left side 10 l is convex and the right side 10 r isconcave such that the main body 10 m, 10 em takes on the shape of aportion of the full stomach that expands from the shape of asubstantially empty stomach. The superior portion 10 s is substantiallylarger and more bulbous than the inferior portion 10 i, since the fundusportion of the stomach 120 expands much more than the antrum uponreceiving food. Thus, as seen in the right side view of FIG. 3B, thesuperior portion 10 s is very bulbous and almost spherical, with alarger cross section than the inferior portion 10 i, while the inferiorportion is more nearly hemispherical, with the center portion of themain body tapering from the superior portion 10 s to the inferiorportion 10 i. Configured as such, the main body 10 m,10 em, whenimplanted properly, will occupy the space that naturally exists from thestomach 120 to expand into when expanding from a pre-prandialconfiguration to a post-prandial configuration. By severely limitingthis expansion capability, the patient is thereby able to consume only asignificantly smaller volume of food than possible if the implant werenot present.

Device 10 sizes will likely vary depending on the size of the skeletalsystem of the patient into which device 10 is to be implanted,particularly the size of the rib cage. Further variations may be made totweak or adjust the amount of restriction along any desired location ofthe stomach that interfaces with device 10. One typical variation is inthe length and/or size (diameter or expandability capacitance) of theinferior portion 10 i. In some embodiments, the inferior portion 10 i ofthe expandable member 10 em may be made longer than shown in FIGS. 3A-3Bto extend further inferiorly and medially than the inferior portion ofthe expandable member shown in FIGS. 3A-3C.

At least a portion of main body member 10 m may be expandable. Theentire main body 10 m may be made of an expandable member 10 em. When inan expanded configuration, expandable member 10 em can optionally onlyabut or lie adjacent to the pre-prandial stomach wall, without impartingany significant deformation forces thereto. However, when the patienteats and the stomach begins to fill, expandable member 10 em in thiscase prevents the stomach 120 from expanding into the volume occupied byexpandable member 10 em. In such a case, the stomach 120 becomes“deformed” as it attempts to expand and can only expand in a limitedfashion, if at all, around a portion of the perimeter of expandablemember 10 em. Thus, upon expanding the device 10, the device 10 expandsin the space(s) normally occupied by the stomach 120 as the stomach 120expands when receiving food. Thus device 10 exerts pressure on, or atleast prevents expansion of the fundus and optionally, the antrum. Inembodiments where the expandable device 10 is not attached to thestomach, the stomach is free to perform its normal function of mixingfood in the stomach for digesting and pushing food out of the stomach.During all of this movement the stomach may slip behind, beside or ontop of the expandable device, but the internal volume of the stomachwill be held to its smaller volume as the expandable device 10 em isoccupying the space into which the stomach would normally expand.Further details of methods for treatment of obesity, includingprocedures for implanting devices described herein are described below.

As noted above, an expandable device 10 can be implanted adjacent asurface of the stomach wall, either in contact therewith or at apredetermined distance therefrom, to prevent expansion of the stomach120 into a volume occupied by the expandable device 10. Alternatively,some embodiments of the devices described herein can be configured andplaced to exert an external compression on one or more locations of thestomach to deform the stomach wall, thereby decreasing the internalvolume of the cavity within the stomach that accepts food and liquidintake. FIG. 4 illustrates (by arrows) potential locations on thestomach 120 wall that can be compressed (or restricted from expanding)by one or more devices 10 as described herein.

In one embodiment, expandable member 10 em shown in FIGS. 3A-3B iscomposed of an inflatable member 10 em. Inflatable members describedherein can be inflated with gas or liquid or both. Examples of gases orliquids that can be used to inflate inflatable members/devices 10include, but are not limited to: carbon dioxide, helium, isotonicdextrose solution, iostonic saline solution, air.

At least a portion of the expandable member 10 em shown in FIGS. 3A-3Bmay be inflated with one or more gases, to provide a relatively lighter,less dense implanted device 10, relative to an expandable membercompletely filled with liquid. The entire expandable member 10 em may beinflated with one or more gases. Alternatively, the entire expandablemember 103 m may be inflated with one or more liquids. Furtheralternatively, devices 10 can be at least partially inflated with aporous gel that is porous or microporous to encapsulate air or other gasbubbles, thereby reducing the weight of the gel while still permittingit to apply volumetric pressure to expand an inflatable member. Suchgels may be settable, such as ultra-violet (uv) curable or otherwisechemically curable, or, alternatively, can remain in the gel state, sothat they can be readily removed or added to, to increase or decreasethe amount of inflation/expansion of the expandable member. Gels can bemade from a flowable viscoelastic substance made of a polymer mixture,such as silicone oil, boric acid, hyaluronic acid, polyacrylic acid orcombinations thereof, for example. The gel, as delivered into theexpandable member 10 em (e.g., such as by injection or the like) can beaerated or infused with carbon dioxide or an inert gas to create adeformable or non-deformable cellular structure that encapsulates thegas in cells, and thus has relatively low mass but still has significantresistance to compression or deformation.

When an expandable member is inflated solely with a pressurized gas,although this reduces the overall weight and density of the device 10,it may tend to be overly buoyant when implanted in a patient. Because apatient is made up primarily of water, the air, carbon dioxide, or otherpressurized gas in expandable member tends to be very buoyant relativeto its surroundings in the abdominal cavity, which are primarily water.Depending upon the orientation of the patient's abdominal cavity at anyparticular time, the buoyancy of such a device 10 may establish a forcethat tends to drive device 10 toward a location away from its intended,predefined location, and may cause the device 10 to tend to migrate awayfrom its intended location to a less desirable position. Also, in thecase of a device 10 having multiple expandable members where one is gasfilled and one is liquid filled, the buoyancy of the gas filledexpandable member may cause it to pull away from a liquid filledexpandable member, particularly if the liquid filled expandable memberis anchored to an internal structure, and this may cause undesirableresults such as unwanted separation of the expandable members and/orfailure of one or more of the expandable members.

Accordingly, it may be desirable to provide a device that has a densitythat is closely matched to the density of its surroundings whenimplanted in the abdominal cavity. Assuming that the abdominal cavityhas a density of saline and is made entirely of saline, then anexpandable member 10 em filled with saline would be substantiallyneutrally buoyant when implanted within the abdominal cavity and wouldnot exert any positive or negative buoyancy forces when implantedtherein. At the other end of the spectrum, if the abdominal cavity werecompletely filled with fat, then a device having an expandable member 10em inflated with an oil matching the density of the fat could beimplanted so as not to create any negative or positive buoyancy forceswhen implanted in the abdominal cavity. In reality, a typical abdominalcavity of a patient will include both water (saline) and fat, withrelative amounts (percentages) of fat varying from patient to patient.Accordingly, device 10 can be designed to have a density somewhere inbetween the density of saline and that of fat, with the amount ofbuoyancy being relatively greater for those abdominal cavities havingrelatively more fat that those having relatively less fat.

FIG. 5A shows an embodiment of device 10 having a buoyancy member 10 bmcontained in the internal chamber of expandable member 10 em. Forexample, buoyancy member 10 bm may be formed of a substantially gasimpermeable material and can be inflated with air, CO₂, or other inertgas to reduce the overall density of device 10 in the expandedconfiguration shown in FIG. 5A. Expandable member 10 em can be filledwith a liquid, such as saline, dextrose solution, or other biocompatibleliquid, for example, and this liquid interfaces with the externalsurface of buoyancy member 10 bm in the expanded configuration shown.Buoyancy member 10 bm can be shaped such that a superior portion thereofhas a curvature that substantially matches the curvature of the superiorend portion of expandable member 10 em, such as shown in FIG. 5A, tothat when inflated and when device 10 is implanted in the patient in theintended orientation and the patient is upright, buoyancy member 10 bmfloats to the superior end portion of expandable member 10 em and fitsin the apex of the superior portion to help secure buoyancy member 10 bmat this location and minimize movement. The position of buoyancy member10 bm within expandable member 10 em orients expandable member 10 emsuch that the superior end of expandable member 10 em is against or nearthe undersurface of the umbrella-shaped diaphragm 116, due to thebuoyant effect of buoyancy member 10 bm on expandable member 10 em.Alternatively, buoyancy member 10 bm may be fixed to the inner surfaceof expandable member 10 em, by adhesives, or buoyancy member 10 bm canbe co-molded with expandable member 10 em. Buoyancy member 10 bm can befixed in the position shown in FIG. 5A in at least one embodiment.

A conduit 12 ₁ can be provided in fluid communication with buoyancymember 10 bm as shown in FIG. 5A, which has a length to allow a proximalend portion thereof to extend out of the body of the patient when device10 is implanted in the desired location and orientation in the abdominalcavity of a patient and expanded. A conduit 12 ₂ can also be provided influid communication with expandable member 10 em, and this conduit alsohas a length to allow a proximal end portion thereof to extend out ofthe body of the patient when device 10 is implanted in the desiredlocation and orientation in the abdominal cavity of a patient andexpanded. As shown, conduits 12 ₁ and 12 ₂ are integrated into a singletube 12 having two lumens 12 ₁ and 12 ₂ until the location where conduit12 ₂ splits off to feed into expandable member 10 em as conduit 12 ₁continues on to join in fluid communication with buoyancy member 10 bmafter passing through the wall of expandable member 10 em. The wall ofconduit 12 ₁ is sealed with expandable member 10 em to maintainexpandable member 10 em at least liquid impervious (and may optionallybe substantially gas impervious). Likewise, conduit 12 ₁ issubstantially gas impervious and joins in a sealed connection withbuoyancy member 10 bm to maintain it as a substantially gas imperviouschamber. Conduit 12 ₂ is at least substantially liquid impervious joinsin a sealed connection with expandable member 10 em to maintain it as asubstantially liquid impervious chamber, optionally as a substantiallygas impervious chamber. Conduit 12 ₁ may run along the surface ofexpandable member 10 em as shown and may be free of the surface ofexpandable member 10 em except for where it inserts through the wall ofexpandable member 10 em. Alternatively, conduit 12 ₁ may be fixed at oneor more locations along its length that is adjacent to expandable member10 em, or the entire adjacent length may be fixed to the surface ofexpandable member 10 em, such as by adhesive, taping, or othermechanical fixation.

Further alternatively, conduit 12 ₁ may extend inside of expandablemember 10 em, as illustrated in phantom lines in FIG. 5A. In this case,conduit 12 ₁ (as well as conduit 12 ₂) may connect with expandablemember 10 em at an inferior location, such as one that is closest to anopening though which device 10 is inserted during implantation, forexample. Further alternatively, conduits 12 ₁ and 12 ₂ may be providedas completely separate conduits along the full lengths thereof.

In one particular embodiment, expandable member 10 em is formed ofsilicone and buoyancy member 10 bm is formed of silicone. However,buoyancy member may include at least one layer, or may be coated with amaterial that reduces the permeability of buoyancy member 10 bm to gaswhen buoyancy member 10 bm is in the expanded configuration shown inFIG. 5A. For example, buoyancy member may include a metallic layer orcoating, such as titanium, silver, or other relatively inert,biocompatible metal. Alternatively, a silicone buoyancy member 10 bm canbe coated with parylene to appreciably reduce gas permeability of thebuoyancy member 10 bm. As another alternative, buoyancy member 10 bm maybe formed by co-extrusion, e.g., co-extruding EVOH (ethylene-vinylalcohol copolymer) and polyurethane to form the buoyancy member 10 bm,with or without a metallic coating as described above. As anotheralternative embodiment, buoyancy member 10 bm may be formed of a blendof silicone and polyurethane. Further alternatively, the buoyancy member10 bm can be formed from or include one or more semi-compliant ornon-compliant materials. Examples of useable semi-compliant materialsinclude, but are not limited to: nylon, polyethylene, polyester,polyamide and polyurethane, see for example, U.S. Pat. No. 6,500,148,which is hereby incorporated herein, in its entirety, by referencethereto. Polyurethane, nylon, polyethylene and polyester can becompliant or semi-compliant materials, depending upon the specificformulation and hardness or durometer of the material as produced.Examples of noncompliant materials that can be used in the constructionof inflatable members described herein include, but are not limited to:polyethylene terepthalate (PET) and urethane. Expandable member 10 emcan optionally be formed in any of the manners described above withregard to buoyancy member 10 bm.

FIGS. 5B-5C schematically illustrate alternative embodiments of buoyancymembers 10 bm, wherein in FIG. 5B, buoyancy member 10 bm comprises aring of gas-filled beads, and in FIG. 5C, buoyancy member 10 bmcomprises a gas-filled coil.

As shown in FIG. 5A, buoyancy member, although it may be variablyexpandable in volume in an expanded configuration, particularly when itis formed of a compliant material, is still somewhat predetermined as toits volume, within a given range, as it will typically be inflated to apredetermined pressure that has been calculated to not stretch the wallsof the buoyancy member to a point where they are unacceptably porous togas leakage. Optionally, a buoyancy member 10 bm may be provided that ismore adjustable in the volume that it can contain, giving the user theability to adjust the buoyancy member over a larger range of volumes soas to adjust the overall buoyancy/density of device 10 in the expandedconfiguration. FIGS. 6A-6C illustrate one version of an adjustablevolume buoyancy member 10 bm that is provided with a “nested chamber”configuration, in which chambers 10 c 1-10 c 4 (although differentnumbers of chambers can be provided, which number may be two, three, ormore than four) can be sequentially expanded, to vary the size of thebuoyancy member 10 bm and thus the volume of gas and amount of buoyancyadded to the overall device 10 that buoyancy member forms a part of.Adjacent chambers can be separated by a baffle or membrane 36 that maybe formed of the same material as the wall of buoyancy member 10 bm, forexample, with each baffle or membrane 36 containing at least one one-wayvalve 38 therein. Valves 38 are configured to open at progressivelygreater pressures, so that the chambers can be opened sequentially andonly to the extent desired, based on the amount of pressure appliedthrough conduit 12.

FIG. 7 illustrates an embodiment of device 10 that includes a buoyancymember 10 bm within expandable member 10 em where buoyancy member 10 bmis formed in the shape of an elongated spine. In this particularembodiment, buoyancy member 10 bm is an elongated tubular member havinga curvature that generally corresponds to the curvature of expandablemember 10 em in the expanded configuration, to follow the contourthereof. Alternatively, buoyancy member 10 bm could be formed as astraight tubular member. In either conformation, the length dimension ofbuoyancy member is such to extend over at least half the length ofexpandable member 10 em or at least two thirds of the length ofexpandable member 10 em or at least three quarters of the length ofexpandable member 10 em. In either the straight or the curveconformation, the length of buoyancy member distributes the buoyancymore equally over the volume of the expanded expandable member, comparedto a buoyancy member 10 bm that is allowed to float to one particularlocation of an expandable member. The embodiment having a curvature thatsomewhat conforms to the curvature of the expanded expandable member 10em has been found to distribute the buoyant forces even better than abuoyancy member having a straight conformation. This distribution of thebuoyancy forces helps to maintain the expanded expandable member 10 emin the desired location, as well as orientation that it is implanted in,as it minimizes any torquing forces or other uneven forces that a lesswell distributed buoyancy member may place on the expanded expandablemember. In this embodiment, like all other embodiments described herein,buoyancy member 10 bm can be sized to provide an amount of buoyancythat, when combined with expandable member 10 em, provides asubstantially neutral buoyancy when implanted in the abdominal cavity ofthe patient. Neutral buoyancy refers to device 10 having a density aboutthe same as the density of the surrounding environment in the abdominalcavity in which the device is implanted. Accordingly, device 10 willthus not tend to either sink or float in the abdominal cavity, but havea tendency to remain substantially in the location implanted.

Alternatively, this embodiment, or any other embodiment describedherein, may be configured to have a slightly positive buoyancy. Thisslight (e.g., less than 0.2 pounds positive buoyancy when implanted,typically much less than 0.2 pounds but greater than zero pounds)buoyancy tends to right the device in a situation where the positivebuoyancy is applied in a superior portion of the expandable member andthe patient is in an upright sitting or standing position, for example.An alternative technique for adding buoyancy, such as to adjust adisplaced device, or that can even be utilized at the originalimplantation of the device, is to input a small quantity of gas into theliquid filled expandable member 10 em. This can be done at the time thatthe expandable member 10 em is filled with liquid, or, for example, on asubsequent patient visit. When done subsequently, the physician mayoptionally withdraw a small amount of liquid to provide space to beoccupied by the small gas volume.

Accordingly, depending on the relative volumes and densities ofexpandable member 10 em and buoyancy member 10 bm, device 10 can: 1)reduce the overall density to reduce the relative “weight” of theimplant within the abdomen (i.e., a neutrally buoyant implant willneither sink nor float but maintain a relatively stable positionrelative to the surroundings in the abdominal cavity); 2) achieveneutral buoyancy within the abdomen; or 3) achieve a slightly positivebuoyancy that helps orient the device 10 upwards into a desired positionand orientation (e.g., located against the fundus and the diaphragm).

In one particular embodiment, the buoyancy member 10 bm of FIG. 7 is aninflatable tube that can be inflated with gas to provide buoyancy. Inone particular embodiment, buoyancy member is a silicone tube that isinflatable with about five to about twenty cc volume of gas. In onespecific embodiment, buoyancy member 10 bm was inflated with ten cc air.Buoyancy member 10 bm may be left free floating within expandable member10 em or may be fixed to an inner wall of expandable member 10 em.Further alternatively, buoyancy member 10 bm may be co-molded withexpandable member 10 em. When buoyancy member 10 bm is not allowed tofree float, but is fixed in some manner relative to expandable member 10em, this may reduce the risk of failure due to wear that might possiblybe caused by repetitive contact between buoyancy member 10 bm andexpandable member 10 em when buoyancy member 10 bm is allowed to freefloat. Buoyancy member 10 bm may be pre-inflated prior to insertionthrough the body of the patient, or even prior to assembly within theexpandable member. Alternatively, a conduit 12 ₁ (shown in phantom linesin FIG. 7) may be provided in fluid communication with buoyancy member10 bm so that buoyancy member can be inflated after device 10 isinserted into the patient, either before or after inflation ofexpandable member 10 em.

FIG. 8 illustrates an arrangement in which a self-expanding buoyancymember 10 bm is provided within expandable member 10 em of device 10.Self-expanding buoyancy member 10 bm can be formed of silicone, or otherbiocompatible elastomer, for example, and can be molded in the expandedconfiguration shown in FIG. 8, with an open inferior end 10 bmo. Sincebuoyancy member 10 bm has an internal chamber or space, the buoyancymember can be compressed or flattened to a much reduced configuration,with a much smaller cross-sectional dimension to facilitate insertionthough a small opening in the patient for percutaneous delivery.Buoyancy member 10 bm has walls of sufficient thickness and elasticitythat when compressive forces are withdrawn, buoyancy member 10 bmautomatically returns to the expanded configuration shown in FIG. 8without the need to input pressurized gas or liquid into the chamber, asthe walls elastically return to the expanded configuration that theywere formed in. This elastic driving force also draws air (or any fluidmedium that opening 10 bmo is in fluid communication with at the time ofthe expansion of the walls) into the chamber of buoyancy member 10 bm.

Accordingly, buoyancy member can be compressed to its compressedconfiguration and expandable member 10 em can be compressed aroundbuoyancy member 10 bm where expandable member 10 em is also in acompressed, non-expanded configuration, so that device 10 is reducedsignificantly in cross-sectional dimension for insertion into a patient.For example, device 10 in the compressed configuration may resemble acylinder. After passing device 10 through a small opening in the patientand into the abdominal cavity (such as through a sheath, for example, orby manually inserting the device 10, while maintaining compression onthe device as it is being stuffed through the small opening) conduit 12that is in fluid communication with expandable member 10 em has aproximal end portion that remains extending out of the patient. Also, aremovable conduit 12 ₁ (shown in phantom lines in FIG. 8) is in fluidcommunication with, and seals off the opening 10 bmo of buoyancy member10 bm. A proximal end portion of conduit 12 ₁ also remains outside ofthe patient when device 10 has been inserted into the abdominal cavityand placed in a desired location and orientation for implantation.However, the proximal end of conduit 12 ₁ need not be connected to apressurized source of gas (although it can be), but can simply be opento the atmosphere (with or without a filter). Thus, when the compressiveforces are removed from device 10, buoyancy member 10 bm self-expands,thereby drawing gas through conduit 12 ₁ which fills the inner chamberof buoyancy member 10 bm. Conduit 12 ₁ can then be detached frombuoyancy member 10 bm and withdrawn from expandable member 10 em andfrom the body of the patient. A one-way valve 10 emv is provided in thewall of expandable member 10 em to seal off the opening through whichconduit 12 ₁ is removed. Optionally, a one-way valve 10 bmv may beprovided in the open end of buoyancy member 10 bm to prevent gas frommigrating into expandable member 10 em. Further optionally, the open end10 bmo and valve 10 emv can be integrated at the wall of expandablemember 10 em. Buoyancy member 10 bm may be free floating or fixedaccording to any of the techniques described above. In one particularembodiment, buoyancy member is bulb-shaped, like the shape of a bulb ona turkey baster, with the bulb portion oriented toward the superior endportion of expandable member 10 em.

FIG. 9 illustrates another arrangement of a device 10 including aself-expanding buoyancy member 10 bm. In this example buoyancy member 10bm is a spherical member that operates in any of the same mannersdescribed above with regard to the embodiment of FIG. 8. The device 10shown in FIG. 10 has a buoyancy member 10 bm that has inner and outerchambers 10 bm 1 and 10 bm 2, respectively. After insertion of device 10into the abdominal cavity, internal chamber 10 bm 1 can be allowed toself-expand or, alternatively, pressurized gas may be inputted to expandthe inner chamber. In either case, gas is inputted through removableconduit 12 ₁. In either case, inner chamber 10 bm 1 is provided with aone-way valve 10 bmv to close off opening 10 bmo after removal ofconduit 12 ₁ to prevent loss of gas to the external chamber 10 bm 2.Conduit 12 ₂ is used to deliver pressurized fluid (e.g., pressurizedsaline or the like) to external chamber 10 bm 2 and then conduit 12 ₂can be removed. All openings in device 10 that conduits 12 ₁ and 12 ₂pass through are closed off by one way valves 10 bmv, 10 emv whenconduits 12 ₁, 12 ₂ are removed. Alternatively, the conduits and valvescan be maintained so that the gas pressure within buoyancy member 10 bmcan be adjusted at a later time. The pressurized liquid in externalchamber 10 bm 2 helps to maintain the gas within internal chamber 10 bm1 and prevent it from migrating out into pressurized chamber 10 bm 2.This is achieved because the pressure within buoyancy member 10 bm 2creates a “structural shell” around buoyancy member 10 bm 1. As thisshell 10 bm 2 is pressurized and takes form, the gas is inputted throughconduit 12 ₁ into the cavity (inner chamber) of buoyancy member 10 bm 1so that there is not a vacuum in the inner chamber, thereby helpingprevent shell 10 bm 2 from collapsing. Cooperatively, buoyancy member 10bm 2, once pressurized, hold open the cavity/inner chamber of buoyancymember 10 bm 1. Depending on the material properties of buoyancy member10 bm 2, gas may be able to permeate out of the cavity of buoyancymember 10 bm 1. However, because of the structure of buoyancy member 10bm 2, the gas will not permeate out to an extent that would create anegative pressure, since energy would have to be expended to force thegas out and create a negative pressure. Expandable member 10 em can beexpanded by inputting pressurized liquid through conduit 12.

In general, for devices 10 described herein, the pressure withinexpandable member 10 em will vary depending upon the material used toform the wall of the expandable member 10 em, as well as the geometry ofthe expandable member 10 em, and whether gas or liquid is used toinflate the expandable member 10 em. For example, an expandable member10 em made of silicone that is inflated with saline typically has aninternal pressure ranging from about 0.25 pounds per square inch (psi)to about 1.0 psi, depending upon the degree of inflation. Because salineis relatively incompressible, expandable member 10 em will hold itsvolume under the pressures of the abdomen. Alternatively, if expandablemember 10 em is filled with a gas, the pressure may be increased toensure that the abdominal pressures do not compress the shape ofexpandable member 10 em, thereby deforming it. The means pressures inthe abdomen typically range between about 0 psi to about 0.4 psi. If aperson is jumping or coughing, abdominal pressures may spike as high asabout 4.0 psi. The buoyancy member 10 bm needs to be designed to thatits shape can withstand the sum of the pressure of expandable member 10em and the at least the mean abdominal pressure (or, preferably, peakabdominal pressure). This can be achieved by designing buoyancy member10 bm to have sufficient structural strength to withstand the sum ofthese pressures. One approach in such design is to provide buoyancymember 10 bm with a hard plastic shell that is structurally strongenough to withstand about 5 psi compression forces. Another approach isto design buoyancy member 10 bm as flexible membrane that self expandsvia a compressible foam. In this case, the foam, upon expanding theflexible membrane of buoyancy member 10 bm, draws air into a chamberdefined by the flexible membrane as the foam expands into it. In thistype of design, the structure of buoyancy member 10 bm needs towithstand the means pressures (e.g., about 2 psi) and, during pressurespikes, buoyancy member 10 bm may deform and rebound after expiration ofthe spike, due to the elastic properties of the foam. Furtheralternatively, buoyancy member 10 bm may be inflated with a gas. In thisarrangement, the gas within buoyancy member 10 bm needs to be able tomaintain a pressure to withstand the peak sums of pressures withinexpandable member 10 em and the abdomen, for example, about 5 psi.

FIGS. 11A-11B illustrate devices 10 that include a substantially rigidbuoyancy member 10 bm. For example, in FIG. 11A, buoyancy member 10 bmis a hollow, substantially rigid sphere, somewhat like a ping pong ball.As long as the outside diameter of buoyancy member 10 bm is less than orpossibly slightly greater than (since tissue is stretchable) a crosssectional dimension of an opening in the patient that device 10 isdelivered through, then the buoyancy member does not need to becompressible. For example, the outside diameter of buoyancy member maybe less than about 50 mm. For example, buoyancy member 10 bm may be madefrom polyethylene, or other relatively low density, biocompatiblepolymer or even thin-walled biocompatible metal. Buoyancy member 10 bmmay be free floating within expandable member 10 em or fixed to an innerwall surface of expandable member 10 em according to any of thetechniques described above. To increase the buoyancy effect, additionalballs or other substantially rigid buoyancy structures may be added,since the overall size of the single buoyancy member 10 bm cannot besubstantially increased in this case, for reasons noted above. FIG. 1Bshows a device 10 that includes a buoyancy member 10 bm having foursubstantially rigid buoyancy members 10 bm 1-10 bm 4, which arespherical in this case, although different shapes may be used, as noted.The buoyancy members 10 bm 1-10 bm 4 are linked in the example shown inFIG. 11B by linking members 11, which may be polymeric or metallicstrands, wires or threads, for example. The chain thus forming thebuoyancy member 10 bm may be free floating as a chain, or fixed relativeto the expandable member 10 em in any of the ways described previously.Alternatively, buoyancy members 10 bm 1-10 bm 4 may be left separatefrom one another and may be free floating, or these separate members maybe individually fixed relative to expandable member 10 em according toany of the previously described techniques.

It is further noted that none of the alternative arrangements describedwith regard to FIGS. 11A-11B are limited to either use of either one orfour buoyancy members 10 bm, as two, three or any number greater thanfour can be used to vary the relative buoyancy, up to a maximum numberthat would substantially completely fill expandable member 10 em in theexpanded configuration. Even with the completely filled arrangement,liquid can still be inputted into expandable member 10 em to fill theinterstices between buoyancy members 10 bm 1-10 bmN (where N equals thetotal number of buoyancy members used). In cases where the number ofbuoyancy members 10 bm used is greater than a maximum number that can bealigned in a single row so that expandable member 10 em can becompressed therearound to form a substantially cylindrical shape fordelivery through a percutaneous opening, the additional number of thebuoyancy members 10 bm over and above that maximum number (oralternatively, all buoyancy members 10 bm) may need to be loaded intoexpandable member after inserting the expandable member (with or withouta portion of the buoyancy members already loaded therein) into theabdominal cavity. In such case, expandable member 10 em can be providedwith a valve or otherwise closable opening 10 emo having a sufficientdiameter to allow buoyancy members 10 bm to be inserted therethrough.After inserting buoyancy members through the incision in the patient(which may include insertion through a sheath or cannula) and intoexpandable member 10 em, expandable member can be sealed to provide aliquid impermeable chamber.

It is further noted that the shape of buoyancy member 10 bm shown inFIG. 11A does not have to be spherical, but can be any other shape thatincludes a sealed off, gas-containing chamber therein and which has amaximum cross-sectional dimension that does not exceed a predeterminedmaximum dimension (examples of which were described above) that wouldprevent it from being inserted (with device 10 compressed therearound)through a small opening in a patient for delivery into the abdominalcavity. FIG. 11C shows one alternative shape in which buoyancy memberhas a substantially cylindrical shape, with a central cavity that sealsgas therein. FIG. 11D illustrates a plurality of the shapes shown inFIG. 11C (i.e., 10 bm 1, 10 bm 2 and 10 bm 3) joined by links 11 to formbuoyancy member 10 bm. Alternatively, these buoyancy members do not haveto be shells, but can be solid and made of a material with very lowdensity, e.g., a foam, sponge or rigid plastic with many air pockets.Substantially rigid plastics can be altered to lower their densities byinfusing them with air bubbles or pockets during their manufacture.Another technology uses micro-hollow glass spheres to reduce the densityof a plastic when infused therein during manufacture. Anotheralternative provides a large number of small plastic hollow spheresencapsulated within a larger shape. For example, a thin walled siliconemember can contain a larger number of small polyethylene hollow spheres,to provide a buoyancy member 10 bm having an overall shape of thesilicone member, with the buoyancy member 10 bm having a densitysubstantially less than that of saline.

FIGS. 12A-12B illustrate another example of a buoyancy member 10 bm. Inthis embodiment, a tubular member 10 bmt is provided that has an annulustherethrough of inside diameter that permits substantially rigidbuoyancy members 10 bm 1, 10 bm 2, . . . , 10 bmN (where N=the totalnumber of buoyancy members) to be loaded therein. For example, tubularmember 10 bmt may be flexible, and may even be expansible so as tostretch somewhat as it is deformed by buoyancy members 10 bm beinginserted therein, when buoyancy members have a slightly greatercross-sectional dimension that the inside diameter of the annulus oftubular member 10 bmt. Alternatively, buoyancy members may be freelyslidable into the annulus without deformation of tubular member 10 bmt,and in this case, tubular member can be flexible or rigid. In oneparticular embodiment, tubular member is formed from silicone, eitherfrom a sheet, or extruded in the tubular shape. In another particularembodiment, tubular member includes layers of EVOH, low densitypolyethylene, and polyurethane to provide an even better gas impermeablebarrier. Buoyancy members 10 bm 1, etc. can be formed the same asdescribed above with regard to FIGS. 11A-11B.

Once the total number of buoyancy members desired have been loaded intotubular member 10 bmt, the ends of tubular member 10 bmt are sealed off,as illustrated in the completed buoyancy member 10 bm shown in FIG. 12B.The spaces in the annulus between the buoyancy members 10 bm 1, . . . ,10 bmN can also hold gas and add to the buoyancy forces generated bybuoyancy member 10 bm. The buoyancy member 10 bm shown in FIG. 12B canbe manufactured into expandable member 10 em, or can be inserted throughan opening such as opening 10 emo, either before or after insertion ofexpandable member 10 em through an opening in a patient and into theabdominal cavity. Buoyancy member 10 bm may be left free floating in thefluid used to expand expandable member 10 em or may be fixed toexpandable member 10 em according to any of the techniques describedpreviously. When tubular member 10 bmt is flexible, it can be bent tofollow the contour of an inside wall surface of expandable member 10 emin the expanded configuration, and fixed to the inside wall surface inthat bent configuration.

FIG. 13 illustrates another arrangement of a buoyancy member 10 bmwithin an expandable member 10 em of device 10. In this arrangementbuoyancy member 10 bm includes a substantially rigid portion 10 bmr andan expandable portion 10 bme. Substantially rigid portion 10 bmr shouldnot have any cross-sectional dimension that is substantially greaterthan a corresponding cross-sectional dimension of a small opening (suchas a small incision, percutaneous opening, or port, for example) thatdevice 10 is to be delivered through during placement into the abdominalcavity. As noted, such dimension may be slightly greater, since the skinand tissues of the patient can be stretched somewhat. In the exampleshown in FIG. 13, substantially rigid portion is tubular in shape withopen ends and may have an outside diameter of one of the specificationsnoted above with regard to FIGS. 11A-11B. Alternatively, thesubstantially rigid portion can have an outside diameter that, when ininserted in a compacted device 10, allows it to be inserted through anincision no greater than about seven cm, or no greater than about fivecm. For example, substantially rigid portion may have a diameter nogreater than about 2.00″, or no greater than about 1.85″, or no greaterthan about 1.5″. In this way, expandable portion 10 bme and expandablemember 10 em can be compressed down around the substantially rigidportion 10 bmr for delivery through a small opening in a patient.Alternatively, the portion 10 bmr can be semi0-compressible such that itcan also be compacted during insertion. However, it can still haveenough structural properties to spring open on its own and therebyprovide supportive structure to open the surrounding portion 10 bme.This compressibility of portion 10 bmr allows it to be designed largerthat the embodiment employing a rigid portion 10 bmr, or, alternatively,allows a smaller incision in the patient required to insert the buoyancymember 10 bm/device 10.

Upon placement of device 10 in a desired location in the abdominalcavity, expandable portion 10 bme can be expanded with a pressurized gassource via conduit 12 ₁. Alternatively, the conduit can simply allow airinto expandable portion 10 bme as portion 10 bmr springs open andexpands portion 10 bme, such that a source of pressurized gas would notbe required to inflate the buoyancy member 10 bm in this embodiment. Itis noted that conduit 12 ₁ can be a permanently placed conduit or it maybe configured to be removable after inflating expandable portion 10 bme,wherein it (and expandable portion 10 bme as well as expandable member10 em) can be configured in any of the manners described in previousembodiments having removable conduits. Expandable member 10 em can beinflated with liquid, such as saline or the like, via conduit 12 ₂.

This arrangement should not require periodic refills of gas intobuoyancy member 10 bm or should at least reduce the frequency with whichgas refills are necessary, since substantially rigid portion 10 bmrmaintains the volume of its shape, thereby maintaining at least apredetermined minimum volume of gas within the buoyancy member 10 bm.Accordingly, even if there is some gas leakage out of expandable portion10 bme, expandable portion 10 bme will never shrink down to a size lessthan the volume occupied by substantially rigid portion 10 bmr, sincesubstantially rigid portion 10 bmr is sufficiently rigid to withstanddeformation forces that can be provided thereagainst by expandableportion 10 bme and/or the liquid pressure of the liquid withinexpandable member 10 em. Buoyancy member 10 bm may be free-floating, asillustrated, or may be fixed at one or more locations to expandablemember 10 em according to any of the techniques described previously.Also, the shapes of expandable, portion 10 bme and substantially rigidportion 10 bmr are not limited to those shown, but may vary. As onenon-limiting example, expandable portion 10 bme may be substantiallycylindrical to follow the contours of a tubular substantially rigidportion 10 bmr.

FIG. 14 illustrates another arrangement of a buoyancy member 10 bmwithin an expandable member 10 em of device 10. In this embodiment,buoyancy member 10 bm is made of foam or other structural arrangementthat encapsulates small gas pockets and therefore does not have to beinflated after placement of device 10 in the abdominal cavity. Althoughshown as a flexible cylindrical structure, buoyancy member 10 bm can beany other shape that lends itself to being inserted through a smallopening in a patient when expandable member 10 em is compressed aroundit. A tubular or cylindrical shape particularly well lends itself tothis task, as the device 10 takes on a somewhat cylindrical shape in thecompressed state where a distal end portion can first be insertedthrough the opening of the patient with the rest of the cylindrical bodybeing pushed through in a direction along the longitudinal axis of thecylindrical shape. Additionally, a tubular shape allows a centralannulus to be closed off to capture and maintain air in the chamberformed by closing the tube off at both ends.

The foam used to make buoyancy member may be a silicone foam, or madefrom polyethylene or other biocompatible polymer for example. In eachcase, the foam is a closed-cell foam having a skin, so that the cells ofthe foam are closed and encapsulate air or other biocompatible gastherein, to ensure that the buoyancy properties of the foam aremaintained and the buoyancy member 10 bm can therefore hold open avolume of gas and displace the liquid in expandable member 10 em. Itshould be noted that some manufacturers denote a “sponge” as aclosed-cell material, and other denote a closed-cell material as a“foam”. Alternatively, an open-cell material may be used, when a layerof encapsulation is established around this open-cell sponge or foam.The encapsulation layer may be dip-molded onto the open-cell structure,or can be manufactured separately and then assembled around theopen-cell structure. Such a configuration utilizes the open-cell foam orsponge to provide structural support to hold open the encapsulationlayer. The encapsulation layer provides a barrier between the gascontained within the open-cell foam/sponge and the saline or otherliquid contained in the expandable member 10 em outside of the buoyancymember 10 bm. An encapsulation layer may be provided over a closed-cellfoam/sponge using any of the same techniques described above. Variousdifferent structural arrangements and shapes of foam as well assponge-like structural arrangements that can be used to make buoyancymember 10 bm are discussed in more detail below. Buoyancy member 10 bmmay be free-floating, as illustrated in FIG. 14, or may be fixed toexpandable member 10 em at one or more locations according to any of thetechniques described with regard to previous embodiments above. Buoyancymember 10 bm has a maximum outside dimension (e.g., outside diameter, orother cross-sectional dimension) that permits it, together with devicecompressed down around it, to be inserted through a small incision in apatient. Examples of such maximum outside dimension are those describedabove with regard to the maximum outside diameter of rigid portion 10bmr in FIG. 13.

In one particular embodiment, the foam is a silicone foam made fromsilicone typically made to make a silicone sheet, but with a foamingagent (sodium bicarbonate, about 1% to about 5% by weight, typicallyabout 5%) mixed with the silicone to make a slurry. This slurry can bedescribed as having a consistency like peanut butter and the slurry ispacked into a mold and then heated at about 150° C. for about an eightyminute cycle. The foaming agent, during the heat cycle, converts towater vapor, carbon dioxide and ammonia, thereby ensuring thebiocompatibility of the resulting foam product. The mold is then removedfrom the heat and allowed to cool. After cooling, the foam product isremoved from the mold and finished by removing any flash that may haveformed. The finished product is a closed-cell foam that includes a skinlayer both inside and outside. In another embodiment, the foam ispolyethylene, which is expanded via high pressure carbon dioxide. Theinfusion of the carbon dioxide creates air pockets that form the foam,leaving a material that remains polyethylene which is thereforebiocompatible.

FIG. 15 illustrates a device 10 wherein buoyancy member 10 bm forms aninternal spine in expandable member 10 em and distributes the buoyancyforces by being shaped proportionally to the expanded shape ofexpandable member 10 em. For example, in FIG. 15, expandable member issubstantially eggplant shaped when in the expanded configuration shown.Likewise, buoyancy member 10 bm is also substantially eggplant-shaped,and is fixed to expandable member 10 em to generally follow the contoursof the expandable member 10 em in the expanded configuration. Thisarrangement substantially distributes the buoyancy forces in a weighteddistribution pattern that matches the weight distribution of the liquidin the expandable member 10 em when it is expanded. Accordingly, thebuoyancy forces are distributed as stably as possible, to minimize anytorquing or other uneven forces that buoyancy member 10 bm mightotherwise apply to device 10 when implanted.

Buoyancy member 10 bm is typically fixed to expandable member 10 emalong the entire length of buoyancy member 10 bm. In the example shown,buoyancy member 10 bm is fixed to an internal surface of expandablemember 10 em. Buoyancy member 10 bm may be made of any of the foamsdescribed above with regard to FIG. 14, and may have a central space 10bmi that runs along the length thereof such that, when joined toexpandable member 10 em, the inner wall surface of expandable member 10em and the walls of buoyancy member 10 bm seal off the internal space tomaintain a gas-filled chamber therein. Buoyancy member 10 bm has amaximum outside dimension (e.g., outside diameter, or othercross-sectional dimension) that permits it, together with devicecompressed down around it, to be inserted through a small incision in apatient. Examples of such maximum outside dimension are those describedabove with regard to the maximum outside diameter of rigid portion 10bmr in FIG. 13. Alternatively, the foam shape of buoyancy member 10 bmmay be compressed such that substantially all of the air inside cavity10 bmi is expelled. The compressed buoyancy member 10 bm then allows theentire device 10 to be compressed down further, overall. This allows foreither a larger outside diameter (expanded) buoyancy member 10 bm to beused, or a smaller incision length. After insertion of device 10 intothe abdominal cavity, the foam can then be allowed to spring open byallowing air or pressurized gas to flow into chamber 10 bmi, forexample, via a conduit 12. The conduit 12 may have a one-way entry andmay be removable, in a manner as described previously.

FIG. 16A illustrates an embodiment of a buoyancy member 10 bm that ismade of foam can be joined to expandable member 10 em as an internalspine member in a manner as described above with regard to FIG. 15.Since the foam is less dense than the material making up the wall ofexpandable member 10 em, its walls can be made substantially thickerthan the expandable member 10 em wall, thereby providing some structuralrigidity as an internal spine, and, at the same time, encapsulating moregas to improve the buoyancy function. Buoyancy member 10 bm can beformed with a hollow core that is open, when molded, and will be closedwhen buoyancy member 10 bm is fixed to expandable member 10 em to sealthe space 10 bmi. Accordingly, the surfaces or edges of the wall 10 bmwaround opening 10 bmi are substantially smooth and conforming to thesurface of expandable member 10 em where they are to be joined. Buoyancymember 10 bm has a maximum outside dimension (e.g., outside diameter, orother cross-sectional dimension) that permits it, together with devicecompressed down around it, to be inserted through a small incision in apatient. Examples of such maximum outside dimension are those describedabove with regard to the maximum outside diameter of rigid portion 10bmr in FIG. 13, although larger maximum outside dimensions may bealternatively used in embodiments where buoyancy member 10 bm iscompressed for the insertion, as noted above. FIG. 16B is across-sectional view of the buoyancy member 10 bm of FIG. 16A takenalong line 16B-16B.

FIG. 17 illustrates a mandrel 20 that is shaped to conform to theopening 10 bmi in buoyancy member 10 bm. Accordingly, after molding thebuoyancy member 10 bm in the form shown in FIG. 16, buoyancy member 10bm can then be stretched over mandrel 20 where is temporarily fixedthereon. A shaft 20 s can be controlled to dip the buoyancy member (onmandrel 20) into a vat of polymer to form a sealing layer or skin overthe external surface of buoyancy member 10 bm to further reduce the gaspermeability thereof. Multiple dips may be performed to form multiplecoats of this skin layer if desired. For example, a vat of silicone maybe provided to dip-mold a layer of silicone over buoyancy member 10 bm.A typical thickness of the layer coated by dip-molding is about 0.005″to about 0.030″. By completely submerging mandrel 20 and buoyancy member10 bm in the molten polymer in the vat, a skin layer 10 bmk (shown inphantom in FIG. 16B) can even be formed over the mandrel portion thatfills the opening 10 bmi. Upon completion of the coating and curing ofthe coating layer, this skin layer can be slit to remove the mandrel 20and the skin layer 10 bmk can then be closed back over by patching witha layer of silicone plus room temperature vulcanizing silicone adhesivefor example. Alternatively, a thin sheet of silicone can be bonded overthe opening in the foam product, using room temperature vulcanizingsilicone adhesive for example. This could optionally be further dippedin silicone to even further ensure sealing. Further alternatively, thisportion of buoyancy member 10 bm can be left open as it will be closedoff by sealing buoyancy member against an inner wall surface ofexpandable member 10 em.

Alternatively, a sealing layer or skin can be molded over the foambuoyancy member by liquid injection molding (LIM). Using this approach,after the foam molded product is removed from its mold, it is insertedinto a second mold that is slightly larger than the mold used to moldthe foam product, but the same overall shape. Liquid silicone is theninjected into the second mold in the space that surrounds the mold tothereby mod a skin layer between the foam product and the walls of thesecond mold. This process may be advantageous in that it can providegreater control over the consistency of the thickness of the skin layerover the foam product, and a single molding step may be performed,rather than repeated dipping steps.

Alternatively, an encapsulation layer may be fabricated separately, forexample, by LIM or dip-molding. This layer can be assembled around thefoam shape, and sealed off to provide complete encapsulation.

Alternatively, the gap 10 bma between the walls 10 bmw leading toopening 10 bmi can be greatly reduced by molding in a shape illustratedin the cross-sectional view of FIG. 16C, to provided a broad flatsurface 10 bmb to increase the surface area to be adhered to the innersurface of a wall of expandable member 10 em. Gap 10 bma may be madesmall enough so that it can be closed by simply compressing thecomponents of 10 bmb together after placing RTV silicone adhesivetherebetween. The gap can be about 0.01″ to about 0.50″, for example, orthe gap can start completely closed, and then slit open to allow theinternal mold to be released, and the slit can then be glued closed. Inthis case, the internal mold needs to be held in position duringmolding, and therefore there will likely be a portion of the internalmold that extends outwards and links to the outside mold. This link willresult in a hold in the foam shape, therefore there may be more than aslit to close. For example, one or two patches may be required to formthe complete closure. Alternatively, the process of bonding the foambuoyancy member to the expandable member 10 em may provide anopportunity to close off the molded openings and the slit.

FIG. 16D illustrates the buoyancy member 10 bmb having been closed byadhering gap 10 bma closed. Alternatively, or in addition thereto, athin sheet of silicone can be bonded over the backing surface 10 bmb,using room temperature vulcanizing silicone adhesive for example. Thiscould optionally be further dipped in silicone to even further ensuresealing. Further alternatively, the gap 10 bma of buoyancy member 10 bmcan be left open as it will be closed off by sealing buoyancy member 10bm against an inner wall surface of expandable member 10 em. FIG. 16Eillustrates a sectional view of the buoyancy member of FIG. 16B in anembodiment where a thin layer of silicone 10 bsi has been bonded overskin layer 10 bmk, using room temperature vulcanizing silicone adhesivefor example, thereby rigidifying buoyancy member 10 bm to fortify itsfunction as an internal spine member, and also providing additionalsealing in of the gas cavity 10 bmi. As noted above, this foam portionof the buoyancy member can alternatively be completely encapsulated in aseparate encapsulating layer.

FIGS. 18A-18J illustrate alternative configurations for formingstructural type buoyancy members, i.e., that do not need to be inflatedor expanded in use, but retain a volume of gas therein to providebuoyancy forces when implanted as part of device 10. Any of thesestructures can be used to make the buoyancy members 10 bm shown in FIGS.14 and 15 for example. FIG. 18A is a construction that includes atubular structure 10 bmw which may be a polymer such as silicone,polyurethane EVOH, or other polymers described herein, as well as layersof one or more of these materials. Other examples include polypropyleneand silicone structure, with silicone foam; or high density polyethyleneor low density polyethylene with silicone. One or more foam struts 10bms (FIG. 18A shows two), are inserted in the open space formed by thetubular structure 10 bmw to increase the overall structural rigidity andresistance to collapse of the tubular structure, while still maintainingsome gas within the foam struts. It should be noted here that thisconstruction does not have to be formed as a tube, or tubular eggplantshape, as the outer wall could be formed as a disk or other structure,for example. The previous statement applies to all of the embodiments inFIGS. 18A-18J.

In FIG. 18B, buoyancy member 10 bm is formed with a foam-like orsponge-like structural arrangement that encapsulates small gas pocketsand therefore does not have to be inflated after placement of device 10in the abdominal cavity. In this example, struts 10 bms are formedintegrally with wall 10 bmw from the same material, which is not a foam,but one or more of the polymers already referred to. Struts 10 bms areseparated by pockets 10 bmg in which gas is encapsulated, as thestructure is completely closed off by walls 10 bmw. Alternatively, theentire mass of FIG. 18B may be “normal” silicone (i.e., not foam) with adesign that has a built-in structure so that it can be compressed, butthen springs open and holds its shape open after being inserted into theabdominal cavity. The air cavity within this structure providessufficient buoyancy to offset the additional density of the “normal”silicone, as compared to foam.

In FIG. 18C, the walls 10 bmw of buoyancy member are supported by tubes10 bmt that may be made of foam, or alternatively may be made of polymersheeting, which may be of the same formulation as wall 10 bmw. In oneparticular embodiment, walls 10 bmw are silicone and tubes 10 bmt areformed of silicone. In another particular embodiment, walls 10 bmt areformed of silicone and tubes 10 bmt are formed of high densitypolyethylene or low density polyethylene. Still further tubes 10 bmt maybe made of silicone foam, polyethylene foam or silicone that is not foam(“normal” silicone). Tubes 10 bmt provide structural support to buoyancymember to keep it from collapsing under pressure imposed by the liquidin expandable member 10 em. At the same time, the annuli in tubes 10 bmtencapsulate gas. Additionally, gas is encapsulated in the walls of thetubes 10 bmt when they are formed of foam. Still further, gas isencapsulated in the gaps or interstices 10 bmg between the tubes 10 bmt.

The embodiment of FIG. 18D may include any of the same materialconstruction configurations described with regard to FIG. 18C. Theembodiment of FIG. 18D however has only a single row or column of tubes18 bmt and this makes the structure less rigid and relatively easier tobend along the longitudinal axes of the tubes 10 bmt.

The bending strength of buoyancy member 10 bm may be modified andtailored by making one or more tubes 10 bmt discontinuous and byaltering the lengths of the discontinuous tube(s) 10 bmt as illustratedin FIG. 18E.

FIG. 18F illustrates a buoyancy member structurally supported by ribs 10bmm molded into the shaped that buoyancy member 10 bm is desired tomaintain. Walls 10 bmw, which may be silicone, for example, completelyencapsulate the ribs 10 bmm thereby sealing the structure andencapsulating gas in the gaps 10 bmg.

In FIG. 18G, a column structure 10 bmc is provided to join opposingwalls 10 bmw and thus provide column strength to buoyancy member 10 bmto maintain it in the configuration shown, thereby maintaining a volumeof gas spaces 10 bmg in which gas is encapsulated. It is noted thatvarious other structure support members may be molded into walls 10 bmwor positioned against the inner surfaces of walls 10 bmw, or otherwisearranged to assist in holding the inner chamber 10 bmi open to maintaina volume of gas to provide buoyancy. For example, any of the types ofstructural members described in provisional application No. 60/877,595to assist in holding expandable member 10 em open (for example, seeFIGS. 9A-15D, 19A and 21-26B) can be used to help maintain the innerchamber of buoyancy member 10 bm open.

In FIG. 18H, a honey-comb-like arrangement of structurally supportingtubes 10 bmt is provided. 10 bmg. This structure can be encapsulated ina layer of polymer such as silicone, polyurethane, polyethylene, EVOH,or the like, or combinations thereof, thereby sealing off the annularspaces of the tubular members as well as the interstices between thetubular members.

FIG. 18I illustrates a foam sheet 10 bmh that can be cut out in atwo-dimensional shape that can then be shaped into a three-dimensionalshape and bonded to an inner surface of expandable member 10 em to forma buoyancy member 10 bm. For example, sheet 10 bmh, could be manipulatedto form an eggplant-shaped buoyancy member bonded to expandable member10 em, like shown in FIG. 15. Clearly, sheet 10 bmh can be cut out toform many other varying shapes of three dimensional buoyancy member whenbonded to the expandable member 10 em. By rolling the edges of the sheet10 bmh and bonding them to an inner surface of expandable member 10 em,an inner chamber 10 bmi is formed that encapsulates gas therein. Thesheet can be encapsulated to provide an additional barrier between thegas within the foam and the saline outside the foam. The encapsulationlayer can be assembled around the foam, or dipped onto it, orestablished by LIM. The encapsulation layer (as well as any otherencapsulation layers or other coatings described herein) can be furthercoated on the outside with a layer of parylene to provide a betterbarrier to fluid permeability.

FIG. 18J illustrates an embodiment formed like described with regard toFIG. 18A (only with one strut 10 bms), but is shown to illustrate moregenerally, that any of the embodiments described above can be molded orotherwise formed with a predetermined curvature designed to conform tothe contour of the inner wall of expandable member (in the expandedconfiguration) to which it is to be fixed. Although shown open ended,both ends of buoyancy member are sealed off in the final product toencapsulate the gas therein.

FIG. 18K illustrates an embodiment wherein sheet 10 bmh is provided withone or more struts 10 bms or tubes 10 bmt (which may be foam or any ofthe other materials discussed above) to provide structure support tomaintain the three-dimensional shape of sheet 10 bmh as it is sealed tothe inner surface of a wall of expandable member 10 em, and to helpmaintain the gas in the chamber formed thereby.

An alternative method of partially or completely foam filling a buoyancymember includes molding the buoyancy member 10 bm in the desired shape,bonding all but an inferior portion of the wall edges 10 bmw to an innersurface of expandable member 10 em, and then inserting a foam insert,either shaped to completely fill the molded buoyancy member 10 bm or toprovide structural supports (struts, tubes, or the like), after whichthe remaining inferior portion of the wall edge 10 bmw can be sealed tothe inner surface of the expandable member 10 em.

FIGS. 19A-19B illustrate two different examples of molded buoyancymembers that can be used as an internal spine like described above withregard to FIGS. 15-16. In FIG. 19A, the foam body of buoyancy member 10bm is molded to have a constantly transitioning increase in outsidediameter/dimension from a small end 11 i through a middle portion 11 mto a large end 11 s. The thickness of wall 10 bmw also graduallyincreases with a tapering increase of thickness from small end 11 ithrough middle portion 11 m to large portion 11 s. Likewise, the insidediameter or dimension 10 bmid that defines the gas cavity 10 bmigradually transitions or tapers from a smallest dimension at the smallend and constantly increases through the middle portion 11 m to thelarge end portion 11 s (where it then necessarily rounds off to closethe end of the buoyancy member 10 bm). In one particular embodiment,buoyancy member 10 bm has an outside diameter or dimension 10 bmod atthe small end 11 i of about 0.85″ which constantly transitions to anoutside diameter or dimension 10 bmod of about 1.85″ at the large end 11s; a thickness of wall 10 bmw of about 0.125″ at small end 11 iconstantly increasing to a thickness of wall 10 bmw of about 0.225″ atlarge end 11 s; and an inside diameter or dimension 10 bmid of about0.60″ at small end 11 i constantly increasing to the largest diameter ordimension of about 1.40″ at the large end portion.

In FIG. 19B, the foam body of buoyancy member 10 bm is molded to have aconstantly transitioning increase in outside diameter/dimension fromsmall end 11 i to middle portion 11 m, and then remains substantiallyconstant from middle portion 11 m to large end 11 s. The thickness ofwall 10 bmw also gradually increases with a tapering increase ofthickness from small end 11 i to middle portion 11 m and then remainssubstantially constant through middle portion 11 m and large portion 11s. Likewise, the inside diameter or dimension 10 bmid graduallytransitions or tapers from a smallest dimension at the small end 11 iand constantly increases to middle portion 11 m and then remainssubstantially constant through middle portion 11 m and large end portion11 s (where it then necessarily rounds off to close the end of thebuoyancy member 10 bm). In one particular embodiment, buoyancy member 10bm has an outside diameter or dimension 10 bmod at the small end 11 i ofabout 1.05″ which constantly transitions to an outside diameter ordimension 10 bmod of about 1.50″ at the middle portion 11 m and thisdimension remains about 1.50″ through to the large end portion 11 s; athickness of wall 10 bmw of about 0.175″ at small end 11 i tapering upto a thickness of wall 10 bmw of about 0.20″, which remainssubstantially constant through the middle and large end portions 11 mand 11 s, respectively; and inside diameter or dimension 10 bmid ofabout 0.70″ at small end 11 i tapering up to a diameter or dimension 10bmid of about 1.10″ at the middle portion 11 m and the large end portion11 s.

Although appearing flat in the two dimensional illustrations of FIGS.19A and 19B, buoyancy member 10 bm may be formed with a twist along itslongitudinal axis, so that the exposed wall edge 10 bmw shown is notplanar, but follows a curvature resulting from the twist that isdetermined to better follow the contour of the inner surface ofexpandable member 10 em. FIG. 16 attempts to illustrate this curvatureresulting from the twist. FIG. 20 also illustrates this curvature, withbuoyancy member 10 bm fixed to the inner surface of expandable member 10em at a portion that twists from the inferior attachment location movingtoward the superior attachment location. It is further noted that thewall of expandable member 10 em can be reinforced in the location wherebuoyancy member is attached thereto, as described in greater detailbelow. While FIG. 20 illustrates what appears to be a curvature in onedimension (in the plane of the paper), the curvature may additionally bein a second dimension (in and out of the paper). Such a complexcurvature may best fit the complex curvature of the inner surface ofexpandable member 10 em where buoyancy member 10 bm is attached. Such acomplex curvature allows the spine/buoyancy member 10 bm to start andend at the most desirable locations to structurally support theexpandable member 10 em. For example, in this embodiment, the startpoint is among the attachment tabs 150 (e.g., see FIG. 22). Thestructure of the spine 10 bm then extends from the abdominal attachmentlocation of the expandable member 10 em to the furthest apex ofexpandable member 10 em and thus performs two functions: 1)spine/buoyancy member 10 bm provides structure which helps to transferthe weight of the cantilevered expandable member 10 em (when anchored tothe abdominal wall) back to the abdominal attachment; and 2)spine/buoyancy member 10 bm provides the most buoyancy at the apexportion/superior portion of expandable member 10 em, so as to minimizetwisting forces and lifting on inferiorly located portions.

FIG. 21 shows an alternative embodiment of buoyancy member 10 bm that ismolded from foam and has a twisted teardrop or eggplant shapedconformation. In this embodiment the walls 10 bmw are thinned down,relative to previous embodiments described, by scalloping to reduce theoverall weight of the molded product. Ribs 10 bmri are molded in toextend from the inside surface of the wall in the locations of thescallops to provide additional rigidity for to hold open the space 10bmi to maintain a desired volume of gas therein to provide buoyancy. Inone particular embodiment, buoyancy member 10 bm is molded from siliconefoam into this conformation. Alternatively, buoyancy member can be madefrom normal silicone, wherein the volume of air in the internal chamberof buoyancy member 10 bm provides sufficient buoyancy to offset theweight of the normal silicone and still provide enough buoyancy to helpoffset the weight of the saline in expandable member 10 em.

FIG. 22 illustrates an embodiment of device 10 having buoyancy member 10bm attached to an inner wall surface of expandable member to form aninternal, buoyant spine in a manner as described above. Expandablemember 10 em further includes a reinforcement layer 160 that extendsover a majority of the length of expandable member 10 em and may extendover substantially the full length of expandable member 10 em. Theportion of the wall of expandable member 10 em covered by reinforcementlayer 160 typically includes at least the area opposite the area thebuoyancy member is attached to, and may include a substantial marginbeyond this area in any direction, up to and including all directions,such as is shown in FIG. 22, for example. Reinforcement layer 160,provides structural support of expandable member 10 em to reduce chancesof the expanded configuration kinking by bending along its longitudinalaxis. Cyclic actions of such kinking can produce wear and even failureof the expandable member, so the addition of reinforcement layer 160performs a useful stiffening function. Together with buoyancy member 10bm functioning as an internal spine, this arrangement of reinforcementlayer 160 and buoyancy member 10 bm provides even more structuralsupport to prevent kinking and otherwise maintain expandable member 10em in its desired orientation in the expanded configuration.

Reinforcement layer 160 may be made, for example, of silicone sheetingreinforced with a strengthening material such as woven polyester,polytetrafluoroethylene, or the like. A margin of unreinforced siliconecan be maintained all around the edges of the sheet to facilitatebonding to expandable member 10 em and to avoid stress concentration atthe edges. Bonding can be performed, for example, using room temperaturevulcanizing silicone adhesive, or vulcanizing a sheet or cut form ofunvulcanized rubber, for example. Alternatively, reinforcement layer 160may be made from a different polymer, such as polyurethane, for example,and reinforced with polyester mesh, for bonding onto a expandable member10 em having a polyurethane outer wall surface.

Alternative formulations from which expandable member 10 em may be madeinclude, but are not limited to: polyurethane compositions includingsilicon-containing chain extenders, such as taught in U.S. Pat. Nos.6,420,452 and 6,437,073, for example, or segmented block polyurethanecopolymers, such as taught in U.S. Pat. No. 5,428,123, or other combinedpolymer compositions of polyurethane and silicone resulting in lesspermeability (to gas and/or liquid) than that of polyurethane usedalone, or silicone used alone. Additionally, these improved barrier(resistance to permeation) properties can be achieved with a thinnerwall thickness than would be required if using polyurethane alone, orsilicone alone. Optionally, buoyancy member 10 bm may also be made fromany of these same materials. U.S. Pat. Nos. 6,420,452; 6,437,073; and5,428,123 are hereby incorporated herein, in their entireties, byreference thereto.

To facilitate anchoring of device 10, device 10 may be provided with oneor more attachment tabs 150. Attachment tab(s) 150 fan out like wingsfrom the surface of expandable member 103 m to provide a much broaderattachment surface area compared to what would be provided by simplyattaching the portion of the expandable member 10 em, from which theyextend, to a structure. FIG. 22 illustrates a single continuousattachment tab 150 that extends from expandable member 10 em about acircumferentially extending portion of the surface of the inferiorportion of expandable member 10 em. Attachment tab 150 may be bonded tothe surface of expandable 10 em, such as with silicone dip layer, forexample, or using room temperature vulcanizing silicone adhesive, orusing unvulcanized silicone sheeting between tab(s) 150 and expandablemember 10 em and then vulcanizing by heat pressing. By bonding to aportion of reinforcement layer 160, stress forces generated by movementsof the patient, for example, through attachment tab(s) which areanchored to the patient, can be distributed over the reinforcement layer160. Additionally, border portions of tab(s) 150 can be sandwichedbetween expandable member 10 em and reinforcement layer 160, therebyfurther reinforcing the connection between attachment tab(s) 150 andexpandable member 10 em. If the attachment tab(s) is/are made frompolyurethane to be bonded to a polyurethane expandable member 10 emwall, a solvent bond can be performed using a slurry mixture ofpolyurethane. By extending the superior edge of tab 150 continuously andintegrally across the width of expandable member 10 em, this strengthensthe bond and eliminates stress concentrations that could lead todelamination of tabs individually bonded to opposite side portions ofexpandable member 10 em.

Alternatively, multiple attachment tabs 150 can be placed at locationsaround expandable member 10 em to extend from and substantially coverareas covered by the larger single attachment tab 150 shown in FIG. 22,although this may introduce locations of stress concentration at thebonded corners of the individual tabs 150 (e.g., peel force attemptingto peel tab 150 away from expandable member 10 em), as noted. However,an advantage is provided by multiple individual tabs 150 in that thetabs are more easily able to conform to the structure that they arebeing attached to, particularly if there is some curvature or othersurface shape other than planar in the structure. That is, tabs 150 canbe overlapped to reduce the overall coverage of the structure to beattached to and this increases the convexity of the attachment surfacesformed by tabs 150, or tabs 150 can be otherwise changed in relativeposition to better match a surface shape to be conformed to, or spreadapart to increase the concavity of the attachment surfaces formed bytabs 150, for example. The overlapping prevents folds or wrinkles thatwould otherwise occur with a single tab 150 such as like that in FIG.22. The use of attachment tab(s) 150 also gives the surgeon the optionto not use conduit 12 to perform an anchoring function. This allows anaccess member connecting to conduit outside of the abdominal wall to beplaced further away from the ribs, potentially offering the patient lessdiscomfort, and also allows conduit 12 to be placed so that it is notunder tension to perform an anchoring function, thereby lessening themechanical requirements for conduit 12. Attachment tabs 150, althoughtypically located to extend from the inferior portion of expandablemember 10 em, need not be so located, but can be placed to extend fromany locations on device 10 or expandable member 10 em.

Tab 150 will typically be formed from a reinforced sheeting, such aspolyester-reinforced silicone sheeting, polypropylene-reinforcedsilicone sheeting or polyethylene-reinforced polyurethane sheeting forexample, or any other biocompatible fabric that can be sandwichedbetween two layers of biocompatible polymers or rubbers. One or morepatches 152 of tissue ingrowth enhancing material, such as a expandedpolytetrafluoroethylene, polytetrafluoroethylene, polyester, etc, infelt or velour configuration, or polypropylene mesh, for example, can bebonded onto the reinforced sheeting so that, when placed in contact withtissue, tissue is encouraged to grow into the patches. An additionaltissue ingrowth enhancing patch 152, such as the circular oneillustrated in FIG. 22 may be provided through which an elongatedpositioning loop 170 may extend, as illustrated in FIG. 23. This tissueingrowth enhancing patch 152 not only encourages tissue ingrowth fromthe tissue location to which it is drawn against by positioning loop170, but also reinforces the junction of positioning loop 170 to device10, strengthening the junction.

FIG. 22 illustrates device 10 including the optional positioning loop170 connected to expandable member 10 em through tissue ingrowthenhancing patch 152 and optionally to reinforcement layer 160.Positioning loop 170 is typically a long lightweight loop of polymer,such as a ribbon and may be formed from polypropylene mesh ribbon or thelike. After inserting device 10 through an opening in the patient andinto the abdominal cavity (positioning loop 170 is also inserted intothe abdominal cavity), a surgeon can form an additional puncture throughthe patient at another location in the abdomen in line with a locationon the abdominal wall where it is desired to anchor the inferior endportion of device 10 to the abdominal wall. This puncture can be veryminimal and performed using a needle, needle that includes a hook, orother sharp, minimally invasive tool. Using the same tool or a differentminimally invasive hook tool or graspers, loop 170 is captured and drawnout through the additional puncture. By applying tension to positioningloop 170, the inferior end portion of device 10 and particularlyingrowth patch 152 can be drawn up against the internal surface of theabdominal wall for anchoring there. Anchoring of the tab(s) 150 can bedone prior to or after inflation of expandable member 10 em. In onetypical example, expandable member 10 em can be expanded with gas orliquid prior to anchoring to facilitate proper positioning of device 10prior to anchoring tab(s) 150. One practical approach is to inflateexpandable member 10 em with gas to check for positioning, sinceinflation with gas is faster and easier than inflation with liquid. Onceproper positioning is confirmed, expandable member 10 em can then bequickly deflated, and anchoring of attachment tab(s) can then beperformed. By performing anchoring of attachment tab(s) with expandablemember 10 em, this provides more working space and/or better visibilityto accomplish the anchoring. After anchoring, expandable member 10 emcan then be inflated with liquid. The ribbon portions of loop 170adjacent the exterior surface of the abdominal wall can be sutured orotherwise fixed to the abdominal wall, and the portions of loop 170proximal of the fixation location can be severed and removed from thepatient.

FIG. 24 illustrates an exploded view of reinforcement tab and loopstructures, demonstrating one method of bonding these structures toexpandable member 10 em. In this embodiment, dual reinforcement layers160 a and 160 b are provided. Positioning loop extends through openingsprovided in the reinforcement/tissue ingrowth patch 152, tab 150 andreinforcement layer 160 b, and the ends of the ribbon 170 are bonded tothe inner reinforcement layer 160 a. Tab 150 is bonded to outerreinforcement layer 160 b and reinforcement/tissue ingrowth patch 152 isbonded to tab 150 or to outer reinforcement layer 160 b. Outerreinforcement layer 160 b is bonded to inner reinforcement layer 160 aaccording to any of the techniques described above for bondingreinforcement layer 160 to expandable member 10 em, thereby sandwichingand securely anchoring the free ends of ribbon 170 therebetween. Theresulting construct can be bonded to expandable member 10 em accordingto any of the techniques described above for bonding reinforcement layer160 to expandable member 10 em.

FIGS. 25A-25C illustrate additional tab features that may be provided ondevice 10, such as on expandable member 10 em to assist inpositioning/repositioning the device in the abdominal cavity. FIG. 25Aillustrates a portion of the outer surface of expandable member 10 em towhich is bonded positioning tab 154. This positioning tab has a base 154b bonded to the surface of the expandable member 10 em and a extendingportion, such as fin 154 e or other tab extension that does not lieflush with the expandable member 10 em surface, but extends therefrom toallow a surgeon to grasp this portion using endoscopic graspers or othertool that can be inserted through a small opening in the patient toperform a grasping function. Once grasped, the tool can be pulled,pushed or otherwise manipulated to move the position of the expandablemember 10 em. The cross sectional view of FIG. 25B more clearly showsthe extending fin portion 154 e of positioning tab 154.

FIG. 25C shows a positioning tab 154 that lies substantially flush withthe surface of expandable member 10 em. However, only the centralportion of tab 154 (bonded portion 154 b) is bonded to expandable member10 em with the borders 154 f left unsecured. Accordingly, graspers orother instrument can grab a portion of the free perimeter 154 f at theborder of positioning tab 154 to apply forces therethrough to move theposition or orientation of expandable member 10. In eitherconfiguration, one or more positioning tabs can be bonded at anylocations on the expandable member 10 em that a surgeon may find usefulto apply leverage to position or orient the expandable member.

FIGS. 26A-26B illustrate an embodiment where tab(s) is/are extended toprovide a shell-like rigidifying support of expandable member 10 em.FIG. 26A shows the anterior surface of tab 150 and expandable member 10em showing tab 150 extending over a majority of the length of expandablemember 10 em. This extended tab 150 can be bonded to expandable member10 em with or without one or more reinforcement layers 160 therebetween,as well as with or without stress relief feature 160F. FIG. 16B showsthe posterior surfaces of tab 150 and expandable member 10 em showingthat tab 150 wraps partially (or optionally, completely) around theposterior surface of expandable member, forming both inferior andsuperior bands 150 b.

FIG. 26C illustrates a configuration where a reinforced frame structureor reinforcement backing layer 160 extends superiorly of tabs 150 andmay be formed in sandwiched, laminated construction with a portion oftab(s) 150 at an inferior portion of the reinforcement backing layer160. A stress relief feature 160F may be provided at the reinforcementlayer 160-expandable member 10 em (optionally, as well as interfaceborders between tab(s) and expandable member 10 em) to diffuse stressconcentrations that would otherwise build up between the backing layer160 and expandable member 10 em, as there is a significant difference incompliance properties between the fabric reinforced backing layer 160and the non-reinforced polymer layer of expandable member 10 em. Forexample, when expandable member is made of silicone and backing layer ismade of polymer fabric-reinforced silicone, stress-relief feature 160Fmay be a bead of RTV silicone, or a cut sheet of unvulcanized siliconesheeting that is pressed and vulcanized to bond to expandable member 10em and backing layer 160.

Tab(s) 150 can be fixed to an internal abdominal structure (such as aninternal surface of the abdominal wall for example) using staples ortacks in a manner as described in co-pending application Ser. No. (Ser.No. not yet assigned, Attorney's Docket No. EXPL-001CIP2), which wasincorporated by reference above, or sutures, or Q-ring fixation membersthat are configured like the coil portion of key ring, that can bethreaded into and through the tab 150 and tissue for anchoring thesetogether, or hooks, barbs, corkscrew type anchoring members, or otherknown anchoring arrangements. FIG. 27 shows an inferior portion ofdevice 10 to illustrate an alternative arrangement for fixing oranchoring tab(s) to an internal abdominal structure, which may be aninternal surface of the abdominal wall and/or other internal abdominalstructure. In this embodiment, sutures 180 are inserted through tab(s)150 at least one location (at least one location into and at least onelocation out of, respectively) to form a loop that can be drawn againstby drawing on the free ends of the suture to draw the tab(s) up againstan internal abdominal structure to be sutured thereto. In the embodimentshown, there are single sutures 180 that pass into, through and out oftab 150 and tissue ingrowth patch at one location in and one locationout. Additionally shown are sutures 180 (in pairs in this example,although this is not necessary) that pas into and out of tab 150 at twodifferent locations, one into and out of a first tissue ingrowth patch152 and a second, into and out of an adjacent tissue ingrowth patch. Itis noted that this arrangement is only exemplary, as other patterns ofsutures 180 could be used to accomplish the method to be describedhereafter. It is further noted, that in embodiments that employ multipleattachment tabs 150, sutures 180 that extend through adjacent tabs 150,when pulled on, can also be used to reposition tabs 152 relative to oneanother prior to fixing them to the internal abdominal structure. Forexample, drawing opposite ends of a suture 180 may draw adjacent tabs150 closer to one another and or cause them to partially overlap.Sutures 180 may be provided with one or more knots or other enlargements182 that cannot pass through the tissue ingrowth patch 152 or tab 150,to prevent sutures 180 from sliding out of the tab(s) 150.

After insertion of device 10 through an incision in the patient and intothe abdominal cavity, the inferior portion can be generally locatedagainst the internal abdominal structure that it is to be anchored to byforming a puncture aligned with that location and retracting loop 170therethrough to pull the inferior portion of device 10 into contact withthe internal abdominal structure, as was described above. It is notedthat positioning loop 170 is not shown in FIG. 27 in order to clarifythe illustration of the sutures 180 shown and the routes into and out oftab 150. Once positioning loop has been anchored extra-abdominally (suchas to the external surface of the abdominal wall, as one example),additional punctures are performed through the skin of the patient tograsp and retrieve ends of sutures 180. Opposite ends of a suture 180are drawn through separate punctures that are generally aligned with thelocations of tab 150 where the particular suture end extends from. Whenboth ends of any particular suture 180 have been drawn through therespective puncture openings, the suture is then tied down by tying thetwo ends of the suture together and forming the tied knot as far downthrough the fat of the patient as possible, into contact with the fascia(or as close to the fascia as possible). This procedure is repeated foreach pair of suture ends of each suture 180.

FIG. 28 schematically illustrates one suture 180 having been tied downto anchor a portion of tab 150 to the inner surface of abdominal wall127. After creating the puncture/small opening 202 through the skin,subcutaneous tissues including fat, fascia 127 and abdominal wall 127and retrieving positioning loop 170 therethrough, positioning loop ispulled to pull the inferior portion of device 10 including attachmenttab(s) 150 against the inner surface of the abdominal wall in a generallocation where it is desired to anchor device 10 thereto. To assist inthis movement, the surgeon may optionally grasp one or more positioningtabs 154 that may be located superiorly of tab(s) 150 on expandablemember 10 em, for example. Further orientation of device 10 may beperformed after the inferior portion of device 10 is drawn against theabdominal wall 127 via positioning loop 170, and this furtherorientation may also be facilitated by pushing, pulling or torquing onone or more positioning tabs 154.

After fixing loop 70 to the outer surface of the abdominal wall 127and/or fascia 127 f and removing the excess loop portion extendingproximally of the fixation point, as described above, an additionalpuncture 204 is formed in a general location overlying a location fromwhich one end of suture 180 exits tab 150. The end is retrieved usinggraspers, or other minimally invasive retrieval instrument and pulledout of the patient's abdominal cavity and through the abdominal wall,optionally all the way out of the patient. Assuming there is at leastone knot 182 formed in suture to prevent it from sliding out of tab(s)150, then the retraction of the first end of the suture can be donewithout concern for holding the other free end of the suture. In thiscase, once the first free end of suture 180 has been drawn out of theabdominal cavity through puncture 204, a second puncture 206 is formedin a location overlying a general location from which the other end ofsuture 180 exits tab 150. the other one end of suture 180. This secondend of suture is then retracted out of the abdominal cavity throughpuncture 206. Alternatively, first and second ends of the suture 180 canbe retracted out of the abdominal cavity simultaneously throughpunctures 204 and 206, respectively. Either way, the two free ends ofsuture 180 are then tied down together as close to fascia 127 f aspossible. The knot formed between the two ends of the suture 180 ispushed down through the fat to be tied off at a location (57 abutting,or as close to the fascia 127 f as possible. This procedure is repeatedfor each suture 180, wherein additional pairs of punctures are createdfor retracting each additional pair of free ends of each additionalsuture 180, respectively.

In an alternative procedure, when pairs of sutures are provided, as inthe arrangement shown in FIG. 27, for example, adjacent free ends of thepairs of sutures 180 can be tied down as close to the fascia aspossible. For example, referring to FIG. 27, a first puncture can bemade to drawn end 180 a therethrough and a second puncture can be madevery close to the first puncture to draw end 180 b therethrough, andthen ends 180 a and 180 b can be tied down together, close to orabutting the fascia 127 f. Similarly, a third puncture can be made todrawn end 180 c therethrough and a fourth puncture can be made veryclose to the third puncture to draw end 180 d therethrough, and thenends 180 c and 180 d can be tied down together, close to or abutting thefascia 127 f. An advantage to this technique is that because the ends tobe tied together are so close to one another, the punctures to draw themout of the abdominal cavity can also be made very close to one another.This results in the tied suture loop 180 surrounding much less fat andtherefore there is a reduced chance of loosening of the tie due to fatloss before sufficient tissue ingrowth has occurred in patches 152.Another advantage is that since the punctures for the adjacent sutureends to be tied can be made so close to one another, they can both bemade from the same incision or puncture in the skin of the patient,while moving the graspers or other puncturing or incising instrumentonly slightly to form a puncture next to one that has already been made.

Alternatively, one or more of sutures 180 can be replaced by additionalpositioning loops 170 that are fixed to tab(s) 150 in locations wherethe ends of sutures 180 would otherwise extend out of tab(s) 150.Anchoring of the tab(s) 150 can then be performed by pulling loops 170out of the abdominal cavity and tying them together in any of themanners described above with regard to sutures 180.

Further alternatively, it is noted that device 10 can be generallypositioned for anchoring the inferior portion of device 10 without theuse of positioning loop 170, with or without assistance of positioningtab(s) 154, and still anchor tab(s) using sutures 180 in any of themanners described above.

Alternatively to separately manufacturing a buoyancy member 10 bm andexpandable member 10 em and then inserting (either with or withoutfixing to the expandable member) buoyancy member 10 bm into expandablemember 10 em (either before or after insertion of expandable member 10em into the abdominal cavity), buoyancy member 10 bm may be manufacturedintegrally with expandable member 10 e. FIG. 29 shows a mold 15 that isthree dimensionally shaped to form expandable member 10 em and buoyancymember 10 bm integrally as a single molded product. Portion 15 em fromthe shape of expandable member 10 em and portion 15 bm extends fromportion 15 em to form the shape of buoyancy member 10 bm. After moldingthe polymeric material over mode 15, a small slit can be made to peelthe molded product off the mold 15. FIG. 30A illustrates the moldedproduct after removing it from mold 15 via slit 10 st, for example. Slit10 st can be closed by patching, such as bonding a sheet of siliconethereover using RTV silicone adhesive, for example, or by bonding withRTV silicone adhesive alone, or other equivalent sealing technique.

By pushing on the portion of the product that will form buoyancy member10 bm in the direction of the arrows shown in FIG. 30A, this portion canbe inverted inside the main body portion that forms expandable member 10em, as illustrated in FIG. 30B. This leaves an open channel or slot 10slt in the wall of expandable member 10 em as illustrated in the rightside view of FIG. 30C. This slot 10 slt can be closed by bonding apolymer layer (e.g., silicone sheet) over it, thereby closing off theinternal chamber 10 bmi and sealing gas therein. Alternatively, prior tosealing, a foam insert having a shape conforming to the buoyancy member10 bm can be inserted therein to hold buoyancy member 10 bm open and, atthe same time encapsulate gas therein. Further alternatively, a balloonor structural supporting elements of any of the types described abovecan be inserted into the inner chamber 10 bmi prior to sealing off theslot 10 slt.

This technique is not limited to formation of a buoyancy member 10 bmhaving a teardrop or eggplant-like shape, but can be applied to manyother shapes of buoyancy members. Likewise, the shape of expandablemember 10 em is not limited to the shape shown. Further, this method isnot limited to the placement of buoyancy member 10 bm as an internalspine as shown. FIG. 31 illustrates an alternative mold 15 in whichbuoyancy portion 15 bm is formed to extend superiorly of the superiorportion of expandable member portion 15 em, and is closer to sphericalshape than eggplant shape. Alternatively, this method of assembling thebuoyancy member 10 bm onto the side area of expandable member 10 em doesnot have to utilize a shape in expandable member 10 em that is inverted.For example, in FIG. 30A, without the shape of 10 bm, the shape of 10 emwould be more like what is shown in FIG. 30B. Given this shape, a flatsheet of foam can be adhered to the outside of the mold for expandablemember 10 em, and a layer of silicone could be layered over the foam toform the expandable member there.

FIGS. 32A-32E illustrate steps that may be carried out during aprocedure for implanting an expandable extra-gastric device 10 accordingto an embodiment of the present invention. Prior to making an incision,the local area (the area of the skin in and surrounding the locationwhere the incision is to be made) may be prepared by disinfecting withalcohol and or betadine. Additionally, the patient may be given a mildsedative or may be on conscious sedation. (Although not practiced inthis particular procedure, a similar procedure could be practiced withplacing the patient under general anesthesia, in which case anestheticswould not need to be injected as described in the next step.) Next apowerful local anesthetic such as marcaine (bupivicaine) or otherpowerful anesthetic, optionally mixed with an epinephrine or othervasoconstrictor to reduce any bleeding that might result from mildtrauma, is injected into the local area through the skin 125 of thepatient 1 down to the muscular layer and to infiltrate the fat layer andentire local area. Injection may be performed using a syringe 219, asillustrated in FIG. 32A, or other injection tool. After allowing timefor the injected anesthesia to take effect, a small incision 223 (e.g.,no greater than about seven cm or no greater than about five cm) is madein the skin 125 of the patient 1, with a scalpel 229 or other surgicalcutting tool, in the local area over the surgical target area wheredevice 10 is to be implanted. In the example shown, the incision 223 ismade slightly inferior to the lower rib line 114. (FIG. 32A shows afrontal schematic view of the abdominal portion of the patient 1).

A delivery tract is then opened from opening 223 through thesubcutaneous tissues and abdominal wall to provide an access openinginto the abdominal cavity. For example, the delivery tract may be formedby starting with a small incision 223, 225 and then inserting a smallport under visual guidance (for example, with VISIPORT™, or the like) toprovide safe access into the abdominal cavity. Alternatively, thedelivery tract can be made with a cannula and a veress-style needlewithin it which is subsequently exchanged, after access into theabdominal cavity, with a wire, such as guidewire 502 or a viewing wireto allow exchange of the cannula and insertion of a larger bore accesssheath over a dilator over the wire. Once the delivery tract has beenestablished, device 10 in a compact configuration is inserted throughopening 223 and advanced along the tract, through the opening in theabdominal wall and placed in the abdominal cavity. FIG. 32B illustratesdevice 10 having been compacted to a substantially cylindricalconfiguration and being fed through the opening 223. This compactconfiguration can be pushed along the tract without any other deliverymechanism. Optionally, a sheath or cannula 17 (shown in phantom lines inFIG. 32B) may be used for delivery of device 10 therethrough.

When the expandable member 10 em has been completely inserted into theabdominal cavity (which can be verified by laparoscope or by otherindirect visualization apparatus for a percutaneous step, or both), andoptionally any buoyancy member 10 bm or insert for a buoyancy member 10bm has been inserted into the expandable member 10 em, (in thosearrangements where a buoyancy member 10 bm or portion of a buoyancymember 10 bm is inserted after placement of expandable member 10 em intothe abdominal cavity) then cannula or sheath 17, if used, is removedfrom the patient and a puncture or very small incision is made in theskin 125 at a location that generally overlies a location of theabdominal wall that the surgeon wants to anchor an inferior portion ofexpandable member 10 em to. The opening through which device 10 isinserted may range from about 5 mm up to about 5 cm, or up to about 7cm. The punctures are much smaller that the opening through which thedevice 10 is passed.

Graspers 784 or other instrument are then inserted through incision orpuncture 225, as illustrated in FIG. 32C, to puncture through thesubcutaneous tissues, fascia and abdominal wall. It is noted here thatif the instrument that is inserted has a sharp distal end, then theinstrument may be used to form the puncture 225 through the skin 125during the same procedural step of puncturing through the subcutaneoustissues, fascia and abdominal wall, thereby eliminating the need for aseparate step to form opening 225. When the distal end of the instrumententers the abdominal cavity, it is maneuvered to capture (e.g., grasp,hook, etc.) positioning loop 170. The instrument is then retracted outof the body of the patient 1 at the same time pulling loop 170 outthrough opening 225 as illustrated in FIG. 32D. Positioning loop 170 ispulled as described above to draw the inferior portion of expandablemember 10 em up against the interior wall surface of the abdominal walland to generally locate it where it is to be anchored. Loop 170 is thenanchored to the external surface of the abdominal wall and/or fascia andthe portion of loop extending proximally from the anchoring location iscut off and removed, as described previously. One or more positioningtabs 154 may be grasped or otherwise used to help move and orient device10 along with positioning by positioning loop 170. For example, anotherset of graspers 784 can be inserted through opening 223 to grasp apositioning tab 154 to assist in movements of the device 10. Also, theinstrument inserted through opening 225 can first grasp or otherwisetemporarily attach to one or more positioning tabs (sequentially) toperform movements of device 10 prior to engaging loop 170 and pulling itout of the abdominal cavity.

When positioning loop 170 has been anchored externally of the abdominalcavity, additional punctures or small incisions are made in order toperform the procedural steps for tying off the sutures 180 (oradditional loops 170 if they are provided to substitute for sutures180). FIG. 32E illustrates eight additional incisions or punctures 225a-225 h made to carry out the anchoring procedures for the sutures 180and/or additional loops 170, for an arrangement of sutures 180 and/oradditional loops 170 shown in FIG. 27. It is noted thatpunctures/incisions 225 c-225 f in this arrangement are used as entrypoints for establishing two adjacent punctures each through the fasciaand abdominal wall.

After completing the tying off or otherwise securing of the sutures 180and/or additional loops 170 is completed and suture material and/orsuture loop material extending proximally from the ties is removed, theincisions/punctures 225 are closed, such as by suturing. An accessmember 80 can be installed according to any of the techniques and in anyof the locations described in co-pending application Ser. No.(application Ser. No. not yet assigned, Attorney's Docket No.EXPL-001CIP2), in provisional application Ser. No. 60/877,595, inapplication Ser. No. 11/407,701, or as described herein. Buoyancy member10 bm, if inflatable can then be inflated with a gas, and expandablemember 10 em can be inflated with a liquid. Opening 223, as well as,optionally, any additional opening that may have been created forinstallation of access member 80 are then closed off, such as bysuturing, to complete the procedure. Alternatively, the buoyancy member10 bm can be integrated with/or double as an anchoring frame 600, asdescribed in more detail below, which may allow for a smaller incisionto be made in the patient, while still providing a buoyancy feature.

FIGS. 33A-33K illustrate steps that may be carried out during aprocedure for implanting an expandable extra-gastric device 10 accordingto an embodiment of the present invention, in which the implantation maybe performed through a single small opening 227 in the patient. Thisopening may be sized to have a length or diameter in the range of about5 mm to about 5 cm, for example, or may have a length or diameter up toabout 7 cm, for example. Prior to making the opening 227, the local area(the area of the skin 125 in and surrounding the location where theincision is to be made) may be prepared by disinfecting with alcohol andor betadine. Additionally, the patient may be given a mild sedative ormay be on conscious sedation. Though not preferred, the procedure canalso be carried out under general anesthesia.

Next a powerful local anesthetic such as marcaine (bupivicaine) or otherpowerful anesthetic, optionally mixed with an epinephrine or othervasoconstrictor to reduce any bleeding that might result from mildtrauma can be injected into the local area through the skin 125 of thepatient 1 down to the muscular layer and to infiltrate the fat layer andentire local area (the anesthetic portion of the mixture may not beneeded if the procedure is performed under general anesthesia).Injection may be performed using a syringe 219, as illustrated in FIG.33A, or other injection tool. After allowing time for the injectedanesthesia to take effect, access to the abdominal cavity is gained byinsertion of a needle 501 (e.g., veress needle) through the skin 125 ofthe patient 1, in the local area generally over the surgical target areawhere device 10 is to be implanted. A conventional veress needle doesnot have a lumen for a guidewire. By adding a small sheath outside theshaft of the veress needle apparatus, a modified veress needle iscreated such that a guidewire 502 can be easily introduced through thesheath. Optionally, this step may be visualized directly via a scope, asneedle 501 can be provided with a scope. For example, a laparoscope 503can be inserted into a trocar 504 (shown in phantom in FIG. 33A) havinga blunt end that can be inserted which has a blunt distal end thatperforms effective separation of tissues as the trocar 504 andlaparoscope 503 are advanced toward and into the abdominal cavity. Byinserting the laparoscope 503 though this blunt-ended port/trocar, thetissues can be visualized as entry is made into the abdomen. When thesurgeon sees intra-abdominal fat, the surgeon knows to stop pushing onthe endoscope, or other instrument, since it is known that the abdominalcavity has been entered. Alternatively, a procedure may be done with acannula, veress-like needle and dilator/sheath as described above.Additionally, or alternatively when scope 503 is note used, this stepcan optionally be visualized under fluoroscopy or other indirectvisualization mechanism.

FIG. 33B is a view of the ribs and stomach 120 with an indication of thelocation on the surface of the skin 125 through which needle 501 andguidewire 502 can be inserted. FIG. 33B illustrates that the location ofinsertion can be well below the xiphoid, to the left of midline, nearthe palpated edge of the costal cartilages (whereas FIG. 33A indicatesthat the insertion can alternatively be performed slightly inferior tothe lower rib line 114, as shown in the frontal schematic view of theabdominal portion of the patient 1).

A dilator, such as an access sheath or cannula 535 having a taperingdistal end portion that gradually increases in outside diameter from adistal end in a proximal direction can optionally be inserted over aguidewire 502, as illustrated in FIG. 33C, after gaining access to theabdominal cavity with a cannula and veress-like needle and exchangingneedle with guidewire 502, in a manner as described above.

FIG. 33D illustrates the insertion of guidewire 502 to follow thecontour of the caudal surface of the left hemisphere of the diaphragm asit is pushed up and around the stomach 120, as far as the spleen. Thedistal end of guidewire 502 may be provided in a “J” shape or other bentshape to make it more atraumatic. Alternatively, a rod may be insertedinstead of guidewire 502, such as a rod that is stiffer than a guidewireand/or that has regions of varying stiffness or flexibility and/or thathas an outside diameter greater than a typical guidewire and which mayoptionally include one or more lumens for fluid injection, suctioning,visualization, etc. Further alternatively, a flexible, steerableendoscope may be inserted in place of guidewire 502 and used as a guiderail for delivery of device 10 (as well as, optionally, other devices orinstruments) thereover and into the abdominal cavity, as described inmore detail in copending application Ser. No. (application Ser. No. notyet assigned, Attorney's Docket No. EXPL-001CIP2) Still furtheralternatively, a flexible wire that is similar in construction toguidewire 502 may be inserted in place of guidewire 502, wherein theflexible wire is only slightly larger in cross-sectional diameter, andincludes one or more optical fibers extending the length thereof, asdescribed in more detail in copending application Ser. No. (applicationSer. No. not yet assigned, Attorney's Docket No. EXPL-001CIP2) Stillfurther alternatively, more than one guidewire 502 or rod or flexiblewire may be inserted. For example, if device 10 is designed to ride overmultiple tracks on anchoring frame 600, then multiple guidewires 502 maybe inserted, one for each track to ride over. Once the guidewire 502 hasbeen placed as desired, needle 501 (if a veress needle 501 is used) ispulled off of guidewire 502 and removed. A dilator 535 can be inserted,or series of increasingly larger dilators 535 can be sequentiallyinserted at this point to enlarge the opening through the patient. Ifdilator 535 was used during the insertion of guidewire 502, thenincreased dilation can be performed by sequential removal andreplacement of one or more larger dilators 535. The last used dilator535 is left in position to function as a port 535.

An anchoring frame 600 and an anchoring frame delivery tool 630 on whichanchoring frame 600 is mounted (in any of the manners described inapplication Ser. No. (application Ser. No. not yet assigned, Attorney'sDocket No. EXPL-001CIP2 or herein) are advanced over guidewire 502 andthrough dilator/port 535 (see FIG. 33E) after which anchoring framedelivery tool 630 is operated to deliver anchoring frame 600 into thetarget position along the abdominal wall, where it is anchored there.Prior to anchoring, the surgeon will check to ensure that no bowel,omentum or other tissue is located between the anchoring frame 600/tool630 and the abdominal wall 127. Optionally, instrument 630 may beprovided with a scope, either flexible or rigid to facilitate directvisualization of delivery and anchoring of the anchoring frame 600.Alternatively, indirect visualization, such as fluoroscopy,electromagnetic visualization mechanisms, or other indirectvisualization systems can be used. Further alternatively, both directand indirect visualization may be used. Anchoring may be performed by avariety of different attachment means, including, but not limited tosutures, staples, adhesives, tacks, needles, or combinations thereof.

After anchoring the anchoring frame 600 to the abdominal wall 127,anchoring frame delivery tool is then removed from dilator/cannula 535and off guidewire 502. FIG. 33F illustrates a sectional view of thepatient 1 (viewed from the feet of the patient) that shows the anchoringof anchoring frame 600 to the abdominal wall 127, with the anchoringframe delivery tool 630 having been removed. FIG. 33G is a schematicillustration from a frontal view perspective, showing the anchoringframe 600 anchored in place against the anterior abdominal wall 127, asalso shown in the sectional view of FIG. 33F.

Once anchoring frame has been anchored to the target location, asillustrated in FIGS. 33F and 33G, a device deployment tool 660 havingalready been preloaded with a device 10 in a collapsed or compressedconfiguration, is next advanced over the guidewire 502 and overanchoring frame 600 in any of the manners described in application Ser.No. (application Ser. No. not yet assigned, Attorney's Docket No.EXPL-001CIP2) or herein, and as illustrated in FIG. 33H. Positioning ofthe device 10 can be monitored during this delivery using fluoroscopy,X-ray, CT or MRI visualization guidance, for example, or simply viadirect visualization with an endoscope, such as a flexible endoscopeinserted through sheath/cannula 535, for example, or extended throughdeployment tool 600, or optionally, though not preferred, throughanother opening provided through the patient's skin and into theabdominal cavity. Device 10 is advanced to the end of anchoring framewhere it automatically locks into position there. Insertion of any ofthe anchoring frame 600 and anchoring frame delivery tool, device 10 anddevice delivery tool, and/or any of the instruments and/or devices usedto access the abdominal cavity are typically performed withoutinsufflation, but may be assisted by what is referred to“mini-insufflation” where the entire abdominal cavity is notinsufflated, as in the typical insufflation procedure, but small burstsof insufflation gas are intermittently inputted to facilitate separationof anatomical structures to help develop the insertion path. Thus, asmall burst could be associated with a small advancement of aninstrument or device, followed by another small burst to help advancethe instrument or device incrementally, and so forth, until the targetlocation has been reached. Alternatively, impulses of liquid (e.g.,saline) can be sprayed to accomplish the same task (e.g., to clear andpath and provide enhanced visibility). Further alternatively, althoughnot preferred, traditional insufflation can be performed. This wouldtypically only be done when the less preferred option of using generalanesthesia is also performed.

FIG. 33I shows a sectional illustration of device 10 having been lockedinto position on anchoring frame 600, with device delivery tool 660having been removed. At this stage, when the surgeon is satisfied thatdevice 10 has been properly positioned and locked to anchoring frame600, cannula/port 535 and guidewire 502 are both removed. At least oneconduit 12 will remain extending will remain extending from device 10,proximally out through the opening 227 for inflation of expandablemember 10 em and, optionally one or more buoyancy members 10 bm when oneor more inflatable buoyancy members are provided. The one or moreconduits 12 can then be used to inflate the one or more buoyancy members10 bm with gas (when buoyancy member 10 bm is of an inflatable variety)and to inflate expandable member 10 em with liquid. Furtheralternatively, one or more conduits may extend through the opening 227to allow a wire, strut, tube or other structural support member to beinserted to support either buoyancy member 10 bm or expandable member 10em, or to insert a buoyancy member 10 bm into expandable member 10 em.

Optionally, expandable member 10 em may be inflated at this stage totest the amount of displacement and positioning of the device 10 when inan expanded configuration, which may help to determine whether device 10will perform as intended. One method of testing in this manner is withthe use of an intra-gastric sizing device 310 (e.g. an intra-gastricballoon catheter) in a manner as described in application Ser. No.11/407,701 and application Ser. No. (application Ser. No. not yetassigned, Attorney's Docket No. EXPL-001CIP2). Additionally, oralternatively, testing may be performed by visually observing theeffects of expansion, such as by inputting radiopaque fluid into thestomach 120, and/or by observing the expansion of the device when it isprovided with one or more radiopaque indicators. Visualization, in suchinstances may be performed fluoroscopically or with other X-rayvisualization, for example.

At this time, any extending conduit(s) 12 can be either clamped off tomaintain the pressures within expandable member 10 em (and optionallybuoyancy member 10 bm), or the pressures can be released, therebyallowing expandable members 10 em (and optionally, buoyancy member 10bm) to at least partially deflate. It is easier procedurally to releasethe pressures and so this is typically done. However, the surgeon maychoose to clamp off the conduit(s) to maintain at least partial pressurein at least the expandable member 10 em to help maintain it in theobserved position/orientation. In any case, conduit(s) 12 is/are nexttrimmed to an appropriate length for connection with an adjustmentmember 80, as illustrated in FIG. 33J.

Conduit(s) 12 are connected to a mating connector on adjustment member80 or to a deployment tool 370 configured to mate conduit 12 withadjustment member 80, and, after connection of conduit 12 to adjustmentmember 80, adjustment member deployment tool 370 is then used to anchoradjustment member 80 to the patient. Adjustment member 80 can beanchored using anchoring members that may be made as any of a number ofdifferent configurations, including, but not limited to: protrudingpins, protruding staples, moly bolt, snap fit with portion placedagainst interior abdominal wall surface; extendable hooks actuated upontorquing a portion of the adjustment member 80 relative to anotherportion, etc. By advancing deployment tool 370 into the patient, theportion of conduit that had extended from the patient 1 is pushed backinto the patient, until the adjustment member is positioned in thetarget location where it is intended to be anchored. This positioningcan be verified using any of the previously described visualizationtechniques, or can be performed blindly, with feedback from palpitation,for example. In the example shown in FIG. 33K, adjustment member 80 isanchored subcutaneously, to the external surface of the abdominal wall127. As has been disclosed previously in applications relied upon forpriority and incorporated herein, adjustment member 80 can alternativelybe anchored subcutaneously, to an inner layer of the skin for example,or otherwise in the fat layer 131 without being anchored directly to theabdominal wall 127.

Once adjustment member 80 has been anchored in the desired location,deployment tool 370 is withdrawn and expandable member 10 em is inflatedwith liquid to expand it to the desired size or pressure, and buoyancymember 10 bm, if it is an inflatable variation can be inflated with gasto a desired pressure. This can be a re-inflation step if the expandablemember 10 em (and optionally the buoyancy member 10 b had beenpreviously inflated for testing and then deflated, or partiallydeflated. In this way, the patient can begin to experience beneficialweight loss from the effects of device 10 on the stomach 120 beginningimmediately after completion of the procedure, unlike currentprocedures, which typically require around six weeks before a returnvisit to “complete” the procedure to make it effective in helping weightloss. The same type or types of monitoring can be used here, asdescribed in application Ser. No. (application Ser. No. not yetassigned, Attorney's Docket No. EXPL-001CIP2), to provide feedback as towhen the expandable member 10 em and/or buoyancy member 10 bm has beenexpanded by the desired amount or pressure. Alternatively, expandablemember may be left in an unexpanded or partially expanded configuration,with the patient being allowed to heal and then return to have theexpandable members 10 em fully inflated. Further alternatively, device10 may be implanted in combination with a constricting band, such as theLAPBAND™ or similar implant to improve results from such constrictingband, or to make weight loss efficacious where prior implantation ofsuch a constricting band has not been efficacious. For example, aconstricting band generally useful for restricting the amount of solidfood ingested by the patient 1. However, a patient 1 may “cheat” theeffectiveness of a constricting band approach by drinking high caloricliquids, for example. For example, a patient could drink a thirty-twoounce milkshake and this would pass right through the constrictionestablished by the constricting band. However, with device 10 implantedand expanded as described, the stomach is preventing from expanding,even by high caloric liquids.

Once the surgeon is satisfied that the expandable member 10 em has beenexpanded by the desired amount and, optionally, the buoyancy member hasbeen inflated to the desired pressure, or, alternatively, if theexpandable member 10 em is to be left in a contracted (unexpanded orpartially expanded) state, the patient is closed, including, suturingthe skin 125 at the site of the opening 227.

Any of the variations of the procedural steps described above may beexecuted under indirect visualization, such as fluoroscopicvisualization, 3-dimensional navigation or other CT/MRI guidance, orethree dimensional RF or electromagnetic visualization (e.g., usingpre-existing or real-time data sets from MRI, cat scan,three-dimensional ultrasound or other three-dimensional data set).Further alternatively or additionally, any of these procedural steps maybe directly visualized using a scope such as a laparoscope or otherflexible or rigid endoscope. A scope may also be integrated into a toolused to perform one or more of these steps.

All tools referenced in the above procedure may include lumens to permitinsertion of other tools and/or devices therethrough, including, but notlimited to: endoscopes, wires, etc. and/or to allow delivery of suction,irrigation, and/or other substances. Alternatively to mounting theadjustment member 80 to conduit 12 in any of the manners describedabove, adjustment member may be pre-attached or integral with conduit12.

No tissues around the stomach area are required to be dissected whenperforming the procedures described above with regard to FIGS. 33A-33K.This also applies to procedures described with regard to FIGS. 32A-32E.This is a major factor in why general anesthesia is not required toperform the procedures, why insufflation is not required, andconsequently why these procedures can be performed in a physician's examroom and are not required to be performed in an operating room Further,with regard to the procedures described with regard to FIGS. 33A-33K, notissue dissection is required other than that to perform the singleentry location through the skin and abdominal wall. The single accessport procedures make this a very minimally invasive procedure. Also, inall procedures described, no stapling or attachment to the stomach isrequired. That is, the stomach 120 is not attached to device 10 in anyway and is free to move relative to device 10 and to the other contentsof the abdominal cavity, except for the constraints provided by thespace occupied by device 10. This greatly minimizes, if not eliminatesproblems of erosion experienced by prior art solutions that do attach tothe stomach or pierce through the stomach wall, as force concentrations,such as shear force concentration are not built up between device 10 andthe stomach 120.

FIG. 34 illustrates restriction of the stomach 120 from expanding to itspost-prandial, expanded configuration by implantation of device 10. Ascan be seen the fundus is substantially restricted from where it wouldotherwise normally expand and the stomach is restrained to a shaperesembling a tube, not dissimilar to a shape resulting from a sleevegastrectomy, but, of course achieved in a very minimally invasivemanner. At least a portion of the antrum 120 a is left unrestrained toallow it to perform its normal functions, such as contractions to movefood into the small intestines by ejecting it from the stomach 120 withmuscular contractions. Additionally, a small pouch 120 p may be left atthe superior end portion of the stomach 120 that provides a smallcapacitance or chamber for receiving food and then signaling the patientthat it is full when this small chamber is filled, similar to afunctionality provided by a banding procedure, such as the LAPBAND™procedure, for example. Under conditions where the stomach is empty(e.g., has substantially no food in it), device 10 may not exert anyadditional pressure (or only minimal additional pressure) to the stomach120. That is the stomach 120 will experience substantially only “normal”abdominal pressures (i.e., close to the pressures that it wouldexperience if there were no implant in the abdominal cavity). Thus,significant forces are only generated between device 10 and the stomach120 when the patient eats.

With regard to procedural embodiments involving the anchoring ofanchoring frame 600 to an internal abdominal structure, FIGS. 35A-35Dillustrate an alternative instrument and method to that described inapplication Ser. No. (application Ser. No. not yet assigned, Attorney'sDocket No. EXPL-001CIP2), e.g., see FIG. 18B and the description thereofin application Ser. No. (application Ser. No. not yet assigned,Attorney's Docket No. EXPL-001CIP2). FIG. 35B illustrates a partial viewof an anchoring frame deployment tool 630, showing a distal portion ofshaft 634 with anchoring frame 600 mounted to distal end portion 634 d.

Shaft 634 articulates, via one or more articulating joints 644 to movedistal end portion 634 d angularly relative to a portion of shaft 634proximal of distal end portion 634 d. An articulation actuator 646 (seeFIG. 35B) is provided on or near handle 632 of tool 600 for operation bya user to control the articulation of distal portion 634 d of shaft 634.In the example shown, articulation actuator 646 is a rotatable wheelthat is rotatable in a first direction to articulate distal portion 634d in a first angular direction about joint 644, while rotation ofactuator 646 in the opposite direction articulates distal portion 634 din the opposite direction. Articulation actuator 646 and/or articulationjoint 644 provide frictional resistance, so that when actuator 646 isnot being rotated, distal portion 634 d is maintained in its orientationrelative to proximal portion 634 p. Alternatively, the straight shaftportion 6349 and articulation feature may be replaced by a curved shafthaving no articulating feature 644.

Distal portion 634 d includes a recess, cavity or slot 650 configured toreceive anchoring frame 600 therein. Thus, recess, cavity or slot 650 isshaped and dimensioned to receive anchoring frame 600 therein and toconfine anchoring frame 600 from movements axially with respect to thelongitudinal axis of distal portion 634 d. Frame 600 may be received inrecess, cavity or slot 650 by friction fit and/or a releasable clampingmechanism 651 maybe optionally provided on opposite sides of slot,recess or cavity 650 for releasably clamping frame 600 wherein it isreceived therein, with clamping and releasing motions being controlledby clamp actuator 653.

In use, after insertion and placement of guidewire 502, such as in aprocedure as described above, deployment tool 630 is passed overguidewire 502, with the proximal end of guidewire first being insertedinto the distal end of shaft 634, through shaft 634 and handle 632 andproximally out of handle 632, as illustrated in FIG. 35B. By insertionof tool 630 into the abdominal cavity, the abdominal wall (e.g., theanterior abdominal wall can be accessed. This portion of the procedure,as well as other steps described below may be indirectly visualizedusing fluoroscopy and/or any of the other indirect visualization methodsdescribed above. Additionally, or alternatively, tool 630 may beconfigured to receive an endoscope 537 (shown in phantom in FIG. 35B)that can be used for direct viewing of the procedure. Thus, endoscope537 can be used to directly view the placement of anchoring frame 600. Avideo camera 538 may be provided on endoscope 537 so as to monitor thevisualization on a screen, or, optionally, viewing may be performeddirectly through an ocular.

A window or opening 648 may be provided proximally of articulating joint644 to enable viewing through the distal end of endoscope 537 that ispositioned in shaft 634 at the location of opening/window 648 whenendoscope 537 is inserted into tool 630. Window/opening 648 may be anopening (e.g., cutout), or may be a window, e.g., a cutout that issealed over with a transparent material.

Visualization, whether indirect, direct, or indirect and direct, isperformed to ensure that there is no tissue located between theanchoring site (e.g., anterior abdominal wall 127) and anchoring frame600 (see FIG. 35A) prior to anchoring the frame 600 to the anchoringsite. Once it has been visually confirmed that there is no tissueintervening between frame 600 and the anchoring site, actuator 646 ismanipulated to rotate distal portion 634 d up against the anchoringsite, thereby contacting surface a contact surface of frame 600 to theanchoring site. Anchors 610 in the form of elongated flexible needles610 n having sutures 59 connected thereto and extending therefrom arenext deployed through openings in the anchoring frame 600, through theinternal abdominal structure to be anchored to (e.g., the anteriorabdominal wall 127 in this case) through the subcutaneous fat layer 131and the skin 125 and therefore out of the patient 1, as illustrated inFIG. 35C. This deployment may be actuated by an actuator 647. Forexample, actuator 647 may be connected to one or more push rods 631 thatabut against ends of needles 610 n to provide a driving force to pushneedles 610 n through the internal abdominal anchoring site and othertissues noted above. Push rod(s) 631 may be flexible, but havesufficient column strength so that it/they do not buckle under thecompression put on them by actuator 647 during deployment, but rathertransfer the compression forces to needles 610 n to move them out of thetool 630 (distal end portion 634 d). Actuator 647 may be connected aboutshaft 634 for relative sliding with respect thereto via slot 647 s.Needles 610 n can be very thin, e.g., like acupuncture needles, and alsohave sufficient column strength to pass through the structures describedwithout buckling.

Needles 610 n are then disengaged from the needle delivery mechanism(e.g., push rods 631). Needles 601 n can be directly attached to suturesthat reside within the channels of the delivery device (not shown). Theback end of the sutures can be looped and held on a hook attached to ahandle on the device to allow retraction of the needles into the deviceif initial deployment was not satisfactory. This hook mechanism can beactuated to release the sutures via a button on the handle when theneedle locations are determined to be acceptable, allowing thesuture/needle units to be pulled by the operation outward until theyengage the anchoring platform. There are many other alternativemechanisms, widely known in the art, to grasp and release a thread likea suture, including mechanisms that cut the sutures from a fixedlocation, mechanisms that open up a clamp that was holding the suturesin a fixed location, mechanisms for releasing a lock on a spool wheresutures are wrapped and initially retained within the deployment device,etc.

Next, the surgeon, pulls the needles 610 n the rest of the way out ofthe patient 1, and continues this retraction until knots or otheranchors (e.g., T-bars, or the like) at the ends of sutures 59 arestopped against anchoring frame 600 Alternatively, sutures 59 may belooped 59 k through anchoring frame 600, so that adjacent pairs ofneedles 610 n are connected to opposite ends of a looped suture 59. Theneedles 610 n are removed from the sutures 59, leaving organized suturesprecisely delivered through anchoring frame and the internal anchoringstructure, precisely deliver through key strategic locations throughanchoring frame 600 designed to optimally secure the anchoring frame 600to the internal abdominal structure. Alternative embodiments may replacethe sutures with other flexible members. For example, polypropylene meshribbons may be substituted. Further alternatively, a combination ofsutures and mesh ribbons may be used, where the flexible member 59begins as a suture where it connects with the needle, and transitionsinto a ribbon. An advantage of a combination such as this is that thesutures are more easily delivered out through the abdominal wall, whilethe ribbons provide potentially better fixation to the abdominal wall.

Sutures 59 may be fixed externally of the abdominal cavity by tying themdown, according to a procedure similar to that described above withregard to FIGS. 27-28 (e.g., by tying two suture ends together to form aloop), or a knot pusher tool 669 can be used to slide a self-lockingclip 667 that can be advanced distally over suture 59 toward theabdominal wall 127, but which is configured to prevent backsliding in aproximal direction, over suture 59 and against the fascia or abdominalwall, or as close thereto as possible as there may be a small amount offat 131 clamped between clip 667 and the fascia/abdominal wall 127,thereby securing a portion of anchoring frame 600 to the internalabdominal structure (in this case, the inner surface of the anteriorabdominal wall 127) by the tension generated in suture 59. The distalend of knot pusher tool 669 may have a sharp edge portion that can beused to cut off the portion of suture 59 that extends proximally fromthe location of clip 667 in its fully advanced position. This cut offportion of the suture and the knot pusher tool 669 are then removed fromthe patient. Each remaining suture 59 is thereafter sequentiallytied/clipped down to securely anchor the entire anchoring frame, therebyforming an array of distributed anchoring forces distributed over theanchoring frame 600.

FIG. 35E is an illustration of the patient's skin 125 with needles 610 nprotruding through openings 228 formed by piercing the needles 610 ntherethrough during performance of the step described with regard toFIG. 26C above. Anchoring frame 600, which has been contacted againstthe anterior internal abdominal wall surface, is shown in phantom. FIG.35F illustrates sutures 509 extending from openings 228 through the skinafter removal of needles 610 n.

FIG. 35G illustrates one embodiment of a suture lock or clip 667installed over a suture 59. Clip 667 can be freely advanced over suture59 in the direction indicated by the arrow, but prevents sliding in theopposite direction, as teeth or cammed surfaces 667 t bite into thesuture 59 if clip is attempted to be slid in the opposite direction,thereby preventing backsliding of clip 667. FIG. 35H illustrates adistal end portion or working end of knot pusher tool 669 being used tolock down a clip 667 in a manner as described above. Tool 669 includes adistal end pusher 669 p configured to interface with a proximal surfaceof clip 667 so as to form a secure engagement therewith as force isapplied therethrough to push clip 667 along suture 59. Tool 669 furtherincludes a cutter portion 669 c proximal of pusher 669 p and throughwhich suture is threaded. Cutter portion 669 c includes a sharp edge orblade 669 b that can be actuated from a proximal end portion of tool 669once clip has been advanced over suture 59 as far as it is going to beadvance to engage the fascia, abdominal wall, or fat near thefascia/abdominal wall. Actuation of cutter edge 669 b cuts through thesuture 59 leaving a short proximal tail that extends from clip 667 by alength about equal to the distance between pusher 669 p and cutting edge669 b.

FIG. 35I illustrates another embodiment of a knot pusher tool 669wherein the cutter portion 669 c is axially aligned with pusher 669 p.Thus suture 59 extend straight through the opening in pusher 669 p andthe opening in cuter portion 669 c out though the central lumen of tool669. Cutter portion includes a V-shaped sharpened edge 669 b that may bebeveled on the underside, so that suture 59 freely passes over the edge669 b as tool 669 is being advanced distally over the suture 59.However, as soon as tool 669 is retracted proximally with respect tosuture 59, the beveled side of sharpened edge 669 b begins to bite intosuture 59 and forces it into the wedge-shape toward the apex of theV-shaped edge, thereby cutting the suture and leaving a tail having alength about equal to the distance between pusher 669 p and the apex ofthe V-shaped cutting edge 669 b.

FIG. 36A illustrates an alternative arrangement of needle 610 n andanchoring member 59 that can be used for anchoring an anchoring frame600 in a manner like that described above with regard to FIGS. 35A-35Iwith variations described hereafter. In order to deploy needles toextend out through the abdomen of a patient 1, needles 610 n may need tobe long enough to extend through the abdominal wall of an obese patient,e.g., on the order of about five inches to about eight inches, typicallyabout seven inches. Accordingly as already noted, needles 610 ntypically require the ability to be bent without plastically deformingas they are redirected from extending in a direction along a length of adeployment instrument, to a direction substantially perpendicularthereto, to deliver needles 610 n through the anchoring frame 600, theabdominal wall 127 and out of the patient 1. FIG. 36A shows only aportion of distal end portion 634 d that contains a radiused portion ofchannel 634 c having a controlled radius to redirect needle 610 nthrough the anchoring frame 600 (not shown in FIG. 36A, for simplicity),without plastically deforming the needle 610 n. For example, needle 610n may be formed of superelastic material, such as nickel-titanium alloy.Needle 610 n may optionally include derailing feature 610 p at or nearthe end opposite the sharp, leading end, that connects to the anchoringmember and that, when contacting the radiused portion, does not enterthe radiused portion, but “kicks out” sideways so that the anchoringportion 59 does not need to be drawn through the radiused portion.Alternatively, the anchoring portion 59 can be drawn through theradiused portion, following the needle 610 n. The device that deploysthe needles may have a mechanism for pushing the needles from aproximally locating starting position, where the starting positions ofthe needle tips are near the locations where they exit the device, andthe needles, being quite long extend proximally along (within) the shaftof the device such that the proximal end of the needles having astarting location with the device shaft that is outside of the abdominalcavity. The mechanism pushes the needles along the device shaft toextend the needles outward to pierce through the abdominal wall. Theneedles have sufficient length so that they are still being pushed bythe mechanism as the needle tips exit the skin of the patient. Once theneedles are fully advanced, they are disengaged from the mechanicalpushing mechanism. The user can then continue to draw the needles out ofthe patient and thereby draw the trailing suture/ribbon out through theabdominal wall. The mechanism for pushing the needles can be mechanicalor pneumatic in nature, powered by energy inputted by the user, or bystored in energy in the mechanism, such as springs or compressed gas.

Needle 610 n may be alternatively connected to a mesh ribbon 59 r, asshown in FIG. 36A, rather than a suture 59. Mesh ribbon 59 r may be madefrom polypropylene mesh, or the like, and may be made to be more durablethan a suture 59, both during assembly of the deployment device, as wellas during deployment of the needles 610 n and ribbons 59 r. Also ribbon59 r has lots of surface area, compared to a suture 59, any portion ofwhich can be easily engaged by barbs. In at least one embodiment, ribbon59 r includes directional barbs 59 b that point away from the end of theribbon 59 r being pulled through the skin of the patient 1. When ribbon59 r has been pulled sufficiently through the abdominal wall to drawanchoring frame 600 against the inner surface of the abdominal wall,release of tension on ribbon 59 r causes barbs 59 b outside of theabdominal wall 127 and nearest to the outer surface of the abdominalwall 127/fascia to catch against the abdominal wall 127/fascia, therebypiercing into the abdominal wall 127/fascia and flaring out radiallysomewhat, as illustrated in FIG. 36H. This securely anchors ribbon 59 r,preventing it from backsliding through the abdominal wall, andmaintaining tension on anchoring frame 600 to hold it against theabdominal wall. The barbs on the ribbons can be large features, or sosmall as to be a microscopic texture that achieves the same effect. Thebarbs can be utilized to engage into the tissue, or, alternatively, thelarge barbs can be used to lock into an externally loaded, washer-likeimplant that ratchets down the barbs and locks in place about thefascia, thereby preventing the ribbon and implant form moving away fromthe fascia. When deploying needles 610 n having mesh ribbons 610 rconnected thereto through the internal abdominal structure to beanchored to (e.g., the anterior abdominal wall 127 in this case) throughthe fascia and subcutaneous fat layer 131 and the skin 125 and thereforeout of the patient 1, after removing needles 610 n from the mesh ribbon59 r portions extending out of the abdomen, mesh ribbons can be anchoredexternally of the abdominal cavity by tying them down, according to aprocedure similar to that described above with regard to FIGS. 27-28(e.g., by tying two mesh ribbons 59 r together to form a loop, orsuture(s) can be used to tie the ribbons 59 r to the fascia wall,optionally using device aids to place sutures, or a knot pusher tool 669can be used to slide a speed nut 667 that can be advanced distally overribbon 59 r toward the abdominal wall 127, but which is configured toprevent backsliding in a proximal direction, over ribbon 59 r, similarto the method described with regard to FIGS. 35G-35I above. Speed nut667 can be advanced against the fascia or abdominal wall, or as closethereto as possible as there may be a small amount of fat 131 clampedbetween speed nut 667 and the fascia/abdominal wall 127, therebysecuring a portion of anchoring frame 600 to the internal abdominalstructure (in this case, the inner surface of the anterior abdominalwall 127) by the tension generated in ribbon 59 r.

FIG. 36B illustrates an embodiment of speed nut 667. Speed nut 667 maybe made of metal, such as stainless steel, nickel-titanium alloy or thelike, or rigid polymer, either resorbable or non-resorbable. Speed nut667 may also be formed from a flexible plastic as long as the grippingfeatures, such as barbs, spears or other gripping features are strongenough to maintain attachment of speed nut 667 to the ribbon or sutureit is anchored to. Speed nut 667 is provided with barbs 667 b, so thatspeed nut 667 can be passed freely over ribbon 59 r in the direction ofthe arrow shown (e.g., toward the abdominal wall), but if an attempt ismade to slide speed nut 667 in the opposite direction relative to ribbon59 r, barbs 667 b engage in the ribbon 59 r, through the holes alreadyexisting in the mesh ribbon, or by creating holes in a non-mesh ribbon,thereby stopping the motion and locking speed nut 667 relative to ribbon59 r with respect to motion in the reverse direction of the arrow shown.Such barbs can be designed as shown, or may have multiple teeth on thetip of each barb. FIG. 36C illustrates a plurality of ribbons 59 rhaving been anchored by fixing speed nuts 667 against the externalsurface of the abdominal wall 127/fascia, optionally with a minimalamount of fat interposed, to distribute anchoring forces over anchoringframe 600 which is drawn against the internal surface of the abdominalwall.

FIGS. 36D-36E illustrate another embodiment of a speed nut 667 that isconfigured to assume undeployed (or extended) and deployed (orcompressed) configurations or states. FIG. 36D shown the uncompressed orextended configuration. In this configuration, speed nut 667 can befreely slid over a ribbon 59 r in both directions. Once speed nut 667 isslid to a desired location with respect to ribbon 59 r, i.e., to alocation where it is desired to lock speed nut 667 with respect toribbon 59 r, speed nut 667 is compressed or deployed to assume thecompressed or deployed configuration shown in FIG. 36E. This compressioncan be performed, for example, using graspers or some other endoscopicclamping tool, or a knot pusher tool may be configured to perform thecompression function. In the compressed configuration, barbs 667 b aredriven radially inwards, thereby piercing into the ribbon 59 r to lockthe position of speed nut 667 relative to ribbon 59 r. At the same time,flanges 667 f extend radially outwardly, thereby increasing the surfacearea against which the anchoring force is distributed, and functioninglike a washer to reduce the risk of pull through of the speed nutthrough the abdominal wall. Additionally, locking features 667 l engageone another, thereby locking speed nut 667 in the compressed/deployedconfiguration. FIGS. 36F-36G show side and perspective views of anotherembodiment of speed nut 667 having multiple barbs 667 b. The distal endportion 667 d has an enlarged face/surface area than the proximal endportion 667 p to help distribute the anchoring forces. Design of any ofthese speed nuts attempts to keep the speed nut 667 to a minimum size tofacilitate it's passage through the needle puncture in the skin, andfacilitating passage through the fat layer, while making at least thedistal end surface sufficiently large so that the speed nut 667 will notpull through the fascia or abdominal wall at the location where it isbeing anchored. In embodiments where the speed nut 667 is metal, theremay not be a locking feature, as plastic deformation of the metal may beutilized instead to transform and hold the speed nut when driven from anundeployed to a deployed state. Further alternatively, speed nut 667,whether made of metal or polymer or some combination, may be providedwith flange elements that extend substantially parallel to the ribbonwhen in an undeployed state, and, once the speed nut is located where itis to lock the ribbon in position relative to the fascia, the flangescan be folded proximally to provide a larger surface area to preventmovement of speed nut 667 through the fascia. Flanges may be bent untilthey collide with features on the speed nut that prevent furtherrotation thereof. This embodiment does not require locking mechanisms orplastic deformation to hold the flanges in their deployed configuration.

In order to provide a wider anchoring frame 600 platform that is notlimited by the diameter of the opening through the patient through whichthe anchoring frame is delivered, anchoring frame 600 may be configuredto be expandable, as illustrated in FIGS. 37A-37B. As shown, anchoringframe 600 includes four expandable arms or beams 600 a. However, thisembodiment is not limited to four beams 600 a as two, three, or greaterthan four beams 600 a may be employed and configured according to thefollowing description to perform similar functions. FIG. 37A illustratesframe 600 in a collapsed configuration in which arms 600 a are collapsedtogether to reduce the cross sectional dimensions thereof to dimensionssmall enough to be passed through the opening (e.g., 225 or 227) in thepatient. Typically, a delivery tool having a tube or cannula 635 isprovided through which the collapsed frame 600 can be slidingly passedfor delivery of the frame 600 into the abdominal cavity. FIG. 37B showsframe 600 in an expanded configuration after delivery through tube 635into the abdominal cavity, where arms or beams 600 a spread apart fromone another, or “fan out” to from the broad-based platform of anchoringframe 600. Beams or arms 600 a may be pivotally 637 connected to oneanother via pivot joints 636 and may be spring-loaded 633 so as tospread apart (in the directions of the arrows in FIG. 37B) when aconstraining force holding the arms or beams in the compactconfiguration of FIG. 37A is removed. Alternatively, arms 600 a may beconfigured to unwind like a clock spring when compression forces of thedeployment device are removed from holding the frame in a compactconfiguration. Further alternatively, arms or beams 600 a maybe spreadapart or radially expanded by plastic deformation to maintain anexpanded configuration. For example, once the frame 600 has cleared thedelivery tool distal end portion 635, arms or beams 600 a may spreadapart.

Arms or beams 600 a are attached to a sheet of tissue ingrowth material602 that folds up, as illustrated (in phantom) in FIG. 37A when beams orarms 600 a are in the collapsed or contracted configuration, and whichare extended into the sheet configuration when arms or beams areextended or fanned out, as illustrated (in phantom) in FIG. 37B. Thistissue ingrowth material 602 is anchored between the beams or arms 600 aand the internal abdominal body structure when anchoring frame isanchored thereto, such as in a manner described above with regard toFIGS. 35C-35H. Thus, needles and sutures are driven through each of thearms or beams 600 a in a manner like that already described.Alternatively, the tissue ingrowth material may be the tabs 150 andtissue ingrowth patches 152 extending from an expandable member 10 em ofa device 10 as described above. In this alternative arrangement,expandable member 10 em is inserted together with anchoring frame 600and anchored directly to the internal abdominal body structure bysuturing through the arms or beams 600 a and the tabs 150/tissueingrowth pads 152 to fix them directly to the internal abdominalstructure.

In either case, beams or arms 600 a are attached to ingrowth material602,150,152 such as by snaps 600 s, or alternatively, by sutures, orother mechanical fixation means. Any of these connections may besupplemented using adhesives, or adhesives alone may be used toestablish the connections. Although not required, it may be preferableto establish connections 600 s on both sides of needle openings 600 nthrough which the needles 610 n pass when performing the anchoringsteps. This is illustrated in the longitudinal sectional views of aportion of an arm or beam 600 a and ingrowth sheet 602,150,152 in FIGS.37C and 37D, where FIG. 37C shows needle 610 n in a retractedconfiguration, and FIG. 37D shows needle 610 n protruding through arm orbeam 600 a and ingrowth sheet 602,150,152. Anchoring frame 600 may alsoinclude a central tube or lumen 600 c (FIG. 37B) that slides overguidewire 502 to guide delivery of the assembly into the abdominalcavity and along the structure to which frame 600 is to be anchored.Alternatively, instead of a guidewire 502, a scope may be used such thatthe scope provides visualization and also provides the guiding utilitywhile positioning the frame 600. Scope may also provide a semi-rigidguiding member for the delivery. Alternative to tube 635, tool 630 maybe provided with a channel 650 sufficiently wide to receive the arms orbeams 600 a in the collapsed configuration. Upon pushing or otherwisesliding frame 600 out of channel 650, arms or beams 600 a expand asalready described. Expansion of arms or beams 600 a may be limited bytravel limits of the pivot joints 633, or may be limited when ingrowthmaterial sheet 602,150,152 is fully extended, thereby ensuring that theingrowth material sheet is maintained under tension to ensure it staysfully spread open.

FIGS. 38A-38B illustrate mating engagement members 600 e, 10 e that canbe provided as part of any of the frames 600 described herein and any ofthe expandable members 10 em described herein, respectively, as well asany of the frames and expandable members described in application Ser.No. (Ser. No. not yet assigned, Attorney's Docket No. EXPL-001CIP2).Further alternatively, and of the frames 600 and expandable members 10em may be provided with any of the interengaging arrangements describedin application Ser. No. (Ser. No. not yet assigned, Attorney's DocketNo. EXPL-001CIP2), e.g. see FIGS. 13A, 13D, 14A-14C, 15A-15C and 19A-19Band the descriptions thereof. Engagement member 600 e in FIG. 38Aprovides for multiple track tracking of expandable member 10 em.Engagement member 600 e includes a pair of rails 618 on opposite sidesof a channel 608 within a rail 618, each of which extend substantiallyover the length of frame 600 (or a beam or arm 600 a thereof). FIG. 38Bshows engaging member 10 e fixed to expandable member 10 em where theengaging member 10 e includes a pair of channels 608 on opposites sidesof a rail 618 that extends from a channel 608, wherein these featuresare configured to mated with the rails 618 and channel 608 of engagementmember 600 e to be slidably received therein (or thereover,respectively) to interengage the expandable member 10 em with theanchoring frame 600. Rail 610 of engagement member 10 e includes acentral lumen therethrough, so that it can be passed over guidewire 502to guide engagement member 10 e into alignment with engagement member600 e to slidingly engage the components together.

Engagement member 10 e can be provided with locks 620 that automaticallylock engagement member 10 e to engagement member 600 e thereby securingexpandable member 10 em in a rotationally and translationally stableposition relative to frame 600. In the example shown, locks 620 arespring loaded and are substantially flush with the channel 608 at distalends thereof, but have proximal ends that angle into the channel 608.The proximal ends are depressed to be substantially flush with thechannel 608 surface as engagement member 10 e, and particularly channel608 is being slid over central rail 618 of engagement member 600 e, asthe proximal ends of the locks 620 are pressed against the rail 618surface. As the component become fully engaged, they are stopped in thedirection of relatively sliding to achieve this engagement by stopsprovided on engagement member 600 e. Engagement member is locked andthereby prevented from sliding in the opposite direction when theproximal ends of locks 620 expand into mating recesses 620 r formed inrail 618. The arrangement of locks 620 and recesses 620 r can bereversed between the components 10 e and 600 e, as would be readilyapparent to one of ordinary skill in the mechanical arts. FIG. 38Cillustrates expandable member 10 em in a compacted, low profileconfiguration for insertion into the abdominal cavity of a patient 1,with the central lumen of rail 618 having been threaded over guidewire502 for sliding delivery and guidance of the device into the abdominalcavity. However, this is just a mock-up, as guidewire 502 is not showninstalled into the abdominal cavity, and that would be performed priorto threading device 10 em onto the guidewire 502. Alternatively,anchoring frame 600 may having buoyancy features integrated therein,which can be desirable to reduce the incision size made in the patientfor insertion of the anchoring frame 600 as well as device 10, sincethis can reduce the overall volume of the implant 10 by moving some ofthe volume (e.g., the volume taken up by a buoyancy member 10 bm) to theanchoring frame 600. Further alternatively, a smaller buoyancy member 10bm can be included in device 10, with a buoyancy member provided in oron anchoring frame 600 to provide combined buoyancy effects.

FIGS. 39A-39C illustrate another embodiment of mating engagement members600 e, 10 e that can be provided as part of any of the frames 600described herein and any of the expandable members 10 em describedherein, respectively, as well as any of the frames and expandablemembers described in application Ser. No. (Ser. No. not yet assigned,Attorney's Docket No. EXPL-001CIP2). In this arrangement, positionadjusting features are provided so that the user/surgeon can selectamount a range of locations for positioning expandable member 10 emrelative to anchoring frame 600. In FIG. 39A, the engagement member 10 ecomprises a spine or rail 618 that is received in a groove or channel608 in anchoring member 600. However, these components could bereversed, with anchoring frame 600 having a spine or rail 618 over whicha channel or groove, provided in expandable member 10 em, can be passed.

An adjustable locking mechanism 20 in this embodiment includes detents622 that are configured and dimensioned to be received in locking holesor openings 624. When detents 622 are positioned through a pair ofopenings 624, this prevents further relative sliding between rail 618and channel 608. An actuator 626 may be provided on either the anchoringframe 600/channel 608, whichever includes the engagement member havingthe detents 622 to, in a first position, temporarily lock the detents ina retracted configuration so that they cannot release and extend throughopenings 624, and, when slid to a second position, release the detents,which are biased, such as by spring-loading for example, so that theydeploy to pass into a pair of openings 624 that they are aligned with.If the openings 624 are not aligned with the detents, the expandablemember 10 em can be slid in one direction or the other, relative toanchoring frame 600 to engage the next adjacent pair of openings 624.

Alternatively, openings 624 may be beveled or tapered to that if detents624 are only partially inserted into openings 624, as illustrated inFIG. 39C, Then rail can still be slid relative to channel 608, asdetents ride in and out of the shallow, beveled portions of openings 624as rail 618 is slid, since the detents 622 are prevented from passingdeeper into holes 24 as long as guidewire or rod 501 is positionedthrough a lumen 623 provided through rail 618. Once the surgeon/user haspositioned expandable member 10 em is a desired location relative to theanchoring frame, as selected from a multiplicity of possible axiallocations along the frame, made possible by the pairs of openingsextending longitudinally over rail 618, guidewire or rod 502 is removedfrom its location with rail 618, allowing detents 622 to slide intolocking positions through openings 624. In this arrangement, detents canbe unlocked again by reinserting guidewire or rod 502 which pushes thedetents back out to the configuration shown in FIG. 39C, allowingexpandable member to be repositioned along the length of the engagementmechanism.

FIGS. 40A-40H illustrate various embodiments of buoyancy members 10 bmthat also function as anchoring frames 600. The embodiment of FIG. 40Aincludes a tubular foam member 10 bmt which may be formed from siliconefoam, or some other polymeric foam, for example. Mesh ribbons 170, whichmay be in the form of looped ribbons or single lengths of ribbons, maybe tied around the tubular member 10 bmt, or suture thereto, or both, orfixed using alternative mechanical fixation structures and/or adhesive.Ribbons (e.g., polypropylene or other polymer) 170 can be pulled throughopenings extending from the abdominal cavity of the patient, out throughthe skin of the patient, to draw buoyancy member/anchoring frame 10bm,600 against the internal surface of the abdominal wall, and ribbonscan be anchored externally of the abdominal wall 127 in any of themanners already discussed previously above. An expandable member 10 emof a device can then be passed over tube 10 bmt and anchored thereto,wherein the buoyancy tube 10 bmt performs the functions of a buoyancymember discussed above, as well as the functions of an anchoring frame600 discussed above. Alternatively, expandable member may be anchored totubular buoyancy member/anchoring frame 10 bm,600 using a dockingtether, as described in more detail below.

FIG. 40B illustrates an embodiment of buoyancy member/anchoring frame 10bm,600 provided with a contact surface 604 having tissueingrowth-enhancing material 616 provided thereon forenhancing/encouraging tissue ingrowth therein from the internalstructure of the abdominal cavity to which contact surface 604 isanchored to (e.g., internal surface of abdominal wall 127).

FIG. 40C shows an end view of the buoyancy member/anchoring frame 10bm,600 of FIG. 40B. FIG. 40D illustrates ribbon loops 170 attached totubular member 10 bmt and extending through backing surface 604 andtissue ingrowth-enhancing material 616 in position to be pulled out ofthe patient to draw buoyancy member/anchoring frame 10 bm,600 up againstan internal body structure to be anchored there.

FIG. 40E is an illustration of a patient showing one example of whereribbons 170 can be pulled through the skin 125 of the patient to drawthe buoyancy member/anchoring frame 10 bm,600 up against the innersurface of the abdominal wall. The X's indicate locations wherepunctures can be made and a hooked tool or graspers can be insertedtherethrough to retrieve ribbons 170 to pull them out of the patient 1,draw the buoyancy member/anchoring frame 10 bm,600 up against the innersurface of the abdominal wall, and lock ribbons 170 down against anexternal surface of the abdominal wall/fascia. It is noted thatoptionally, at least one of the ribbons can be drawn though anintercostal space, as shown in FIG. 40E.

FIGS. 40F-40G illustrate features for anchoring the expandable member 10em to the buoyancy member/anchoring frame 10 bm,600 according to onemethod embodiment. In this embodiment, buoyancy tube 10 bmt is providedwith an annular opening therethrough. After anchoring the buoyancymember/anchoring frame 10 bm,600 to an internal abdominal structure,such as the abdominal wall, in a manner as described above, a guidewire502 or snare catheter 502 can be inserted through the lumen of tube 10bmt as shown in FIG. 40F. The expandable member 10 em of device 10 canbe provided with a docking tether 59 d, such as a braided mesh polymertether, woven polymer tether or ribbon, for example. Docking tether 59 dcan be fixed to a superior portion of expandable member 10 em and has afree opposite end having a docking connector 59 c. An inferior portionof expandable member 10 em is provided with a mating connector 59 m thatis mateable with docking connector 59 c to form a locked connection. Inthe example shown, docking connector 59 c comprises a male luerconnector and mating connector 59 m comprises a female luer connector.However, these could be reversed. Further alternatively, other types ofmating, mechanically connectable members could be substituted.

After placing expandable member 10 em into the abdominal cavity (in anon-expanded configuration), guidewire 502 or snare catheter 502 s isused to capture the free, proximal end of docking tether 59 d. Thecaptured free end is then into the distal end opening of tubular member10 bmt, through the annular space in tube 10 bmt and out of the proximalopening. Connector 59 c is then connected to mating connector 59 m,thereby locking the free end of docking tether 59 d to expandable member10 em and anchoring expandable member 10 em to buoyancy member/anchoringframe 10 bm,600 as illustrated in FIG. 40H.

On advantage of using a dual-function buoyancy member/anchoring frame 10bm,600 is that it is a low profile system, since the buoyancy member 10bm and expandable member 10 em do not require simultaneous insertioninto the abdominal cavity. Further, a dual-function buoyancymember/anchoring frame 10 bm,600 is very lightweight and therefore mayreduce potential complications during the tissue ingrowth periodrequired for tissue for tissue from the anchored-to structure to growinto the anchoring frame. This can be particularly advantageous insituations where buoyancy member/anchoring frame 10 bm,600 is anchoredby itself and allowed a tissue ingrowth period before fixing anexpandable member thereto, or in situations where the expandable member10 em is initially fixed to buoyancy member/anchoring frame 10 bm,600,but is not inflated or only partially inflated with liquid during thetissue ingrowth period.

FIG. 41 shows examples of implant markers and sensors that may beincluded on device 10. Any combination of implant markers and sensorsshown, including a single marker or sensor, up to and including allmarkers and sensors shown, may be included on any of the devicesdescribed herein, in the locations shown (or corresponding locations fordifferent embodiments of devices 10). Additionally, these features arenot limited to the locations shown, but can be included at otherlocations, such as, but not limited to: anywhere along one or moreconduits 12, attachment tab(s) 150, positioning loop(s) 170, anylocations on anchoring frame 600 or corresponding components thereof,etc.

Markers 420 may be provided at various locations on device 10 that aretrans-abdominally detectable, for example, using fluoroscopy (radiopaquemarkers), ultrasound (ultrasonically detectable markers),three-dimensional navigation (magnetic or RF sensors) for indirectvisualization/tracking of device 10 during the implantation procedure,as well as after device 10 has been implanted and the procedure has beencompleted. These markers can be present on the surface of device 10 ormay be embedded beneath one or more layers of material, or molded withina layer, for example. Additionally, or alternatively, visual indicators422, such as text, arrows or other graphical markings or visuallydetectable indicators can be provided for direct viewing by laparoscopy,for example. Indicators 422 may also be provided with contrasting colorsto make them easier to locate relative to the portion of device 10 thatthey are located on.

The material(s) making up all or a portion of device 10 may be dopedwith radiopaque material to facilitate identification thereof byindirect viewing such as fluoroscopy or other X-ray. Markers 420 and/orindicators 422 may also be used to assess function. For example, themarkers 420 identified by “S” and “I” in FIG. 41 may be viewed and adistance therebetween measured to assess the amount of expansion/fillingof expandable member 10 em that has occurred. Markers 420 canadditionally or alternatively be used as sensors to provide feedback tomeasure relative position of device 10, pressure within expandablemember 10 em, motility of device 10, volume occupied by device 10 orexpandable member 10 em, etc. Markers 420 may be detectabletrans-abdominally using known sensing modalities such as magnetic, RF,X-ray, ultrasound or auditory signals. Markers 420 may also beconfigured to emit/transmit RF, ultrasound or auditory signals, forexample. Thus, marker(s) 420 and/or indicator(s) 422 can be used to givethe surgeon or other person feedback during, as well as after completionof the implantation procedure, as to location of device 10 and/orfunctionality thereof.

As one example of use of markers 420 for three-dimensional navigation ofthe delivery and placement of device 10 during an implantationprocedure, a pre-existing “map” of the internal structures of a patient1 may be provided in the way of a CT scan, for example, so that asurgeon can study this map prior to the procedure and identify the bonystructures around the abdominal cavity, to be used as landmarks duringthe procedure to help in navigating/directing device 10 and associatedtools to one or more desired target locations in the surgical site.Although soft tissues will be mobile, the surgeon can identify targetlocations relative to the bony landmarks.

At the beginning of the procedure, typically, prior to making anincision, the actual bony structures of the patient 1 (as visualizedunder fluoroscopy, for example, or palpation to identify pre-determinedregistration points) are registered to match the locations of the samestructures on the pre-existing map, which can be displayed on a monitor,for example. During the procedure, the markers 420, whether detected byfluoroscopy, magnetic detection, RF detection, ultrasound detection,etc. are displayed on the monitor overlaid on the pre-existing map towhich the bony structures of the patient 1 have been registered.Accordingly, the surgeon/user can view in real time, a three dimensionalimage of the location of markers 420 relative to the landmark bonystructures, to guide the surgeon/user to deliver device 10 along adesired pathway and place and implant device 10 in the desired targetlocation.

Not only can device 10 be navigated in this manner, but any otherinstruments or devices inserted into the patient 1 during the procedure,can also be navigated in similar fashion. For example, insertion andplacement of guidewire 502, prior to insertion of device, can be guidedand navigated by provided a distal tip or distal end portion ofguidewire with a sensor 420. Other tools and devices can be navigatedsimilarly.

Sensors 420 may be passive and/or active. For example, sensors 420 cansimply be magnets or radiopaque markings, which are passive sensors thatare detected by instrumentation outside of the body of the patient.Alternatively, sensors 420 may be active, such as sensors that transmitRF signals, or other electrical signals, for example. Furtheralternatively, sensors 420 may have both passive and active functions. Asensor may be “pinged” by instrumentation outside of the patient's bodyand reflected waves returned from the sensor being pinged can betriangulated by feedback from external sensors to determine the locationof sensor 420. Sensor 420 may include an antenna and processor that caninstruct it to emit a signal when a particular instruction has beenreceived by the antenna. Any of the sensing and/or navigation methodsdescribed above can optionally also reference the stomach 120, such asby fluoroscopy or X-ray when radiopaque contrast fluid is inputted intothe stomach.

One or more sensors 420 may also be used for the performance of one ormore procedural steps robotically. As one non-limiting example of this,FIG. 42 illustrates a procedural step for anchoring anchoring frame 600to an internal surface of abdominal wall 127 using ribbons 170. Arobotic arm 700 having a controllable module 702 that is controllable tomove a working tool 704 (in this case, a hooked needle) in threedimensions is provided over that patient 1. Module 702 is first moved intwo dimensions parallel to the skin of the patient (i.e., in thedimensions of the arrows shown and the dimension into and out of thepage) to align sensor 706 with a sensor 420 on anchoring frame 600 thatis aligned with one of the ribbons 170. Once this alignment has beenconfirmed, tool 704 is then robotically driven into the patient 1 topierce the skin 125 and to a depth to engage loop 170 with the hookedportion of the needle 704. Tool 704 is then retracted back out of thepatient to pull a portion of the ribbon 170 out of the skin 125.Tensioning of the ribbon 170 and anchoring it to an external surface ofthe abdominal wall/fascia 127 can optionally also be performedrobotically. It is noted that this is only an example of a roboticprocedural step that can be performed, as virtually any and allprocedural steps described herein can be performed robotically, usingthe sensing and control techniques described herein.

FIG. 43 illustrates a handheld device 720 configured to communicate withone or more sensors 420 located internally of the patient, such as ondevice 10 (and/or anchoring frame 600, conduit 12, etc.) Handheld devicemay be powered by a power cord 722 that plugs into an electrical outlet,or may be battery powered, and thus more portable. Device 720 may beoperated by a treating physician, or by the patient himself, forexample. In the example shown, device 10 includes two expandable members10 em ₁ and 10 em ₂, each provided with a pressure sensor 420 configuredto receive a wirelessly transmitted signal from handheld device 720,and, in response thereto, transmit a wireless signal (e.g., RF signal orthe like) to handheld device to indicate the current pressure reading.Other sensing capabilities that may be provided include, but are notlimited to: sensing of stomach motility via electrical signals or motionsensors or stretch detectors; pressure sensing; temperature sensing;oxygenation sensing; sensing of grehlin or other hunger or satietymarkers. Upon reading the signals from sensors 420, device 720 displaysthe sensed pressures on display 724, for example. These readings canprovide useful information to the patient 1 and/or physician as towhether an expandable member(s) has sufficient pressure or is over orunder inflated, for example and thus whether a pressure adjustment needsto be made. Additionally, these readings can identify a leak in thedevice and alert the user thereto, without the need for initial checkingby X-ray or more invasive means. Device 720 may also be connectable tothe Internet, for example, by wireless communication, and may beprogrammed to email a physician when used by the patient 1 and when oneor more readings is not within expected ranges, thereby alerting thephysician that the patient needs to be seen in the physician's office tocorrect a problem with the device 10.

FIG. 44 illustrates an example where a surface of expandable member 10em is provided with sensors 420 comprising electrodes that can be usedto deliver pacing signals to the stomach from a subcutaneously placedpacer/stimulator 428 that communicates via wires 429 or wirelessly withelectrodes of sensors 422. Sensors 422 may also function as pressuresensors and send signals representative of pressure readings topacer/stimulator 428. Accordingly, when signals are received thatcorrespond to pressures greater than a predetermined pressure level(e.g., indicative of food having been inputted to the stomach 120) thiscan initiate a pacing program in the pacer/stimulator to sendcoordinated stimulation signals to the electrodes 420 to increase ordecrease motility caused by contraction of stomach muscles resultingfrom the pacing signals applied by the electrodes 420.

FIG. 45 illustrates another embodiment of device 10 in which wiring 429extends through conduit 12 to be connected to pacer/stimulator 428. Inthis case, pacer/stimulator 428 may be incorporated into access member80 or subcutaneously implanted adjacent access member 80, for example.Although device 10 is shown to include two expandable members 10 em ₁,10 em ₂, this arrangement may be applied equally as well to deviceshaving a single expandable member 10 em (with or without buoyancy member10 bm) or more than two expandable members. Further alternatively,sensors 420 in either FIG. 44 or FIG. 45 may not provide pressuresensing feedback, but may be only electrodes for applying the pacingsignals. In such case, pacer/stimulator 428 may be controlled manuallyby the user or physician, either wirelessly, or by plugging a controllerinto a socket provided in access member 80, or on the skin 125 of thepatient, for example, to apply pacing signals to the electrodes 420.

While the present invention has been described with reference to thespecific embodiments thereof, it should be understood by those skilledin the art that various changes may be made and equivalents may besubstituted without departing from the true spirit and scope of theinvention. In addition, many modifications may be made to adapt aparticular situation, material, composition of matter, process, processstep or steps, to the objective, spirit and scope of the presentinvention. All such modifications are intended to be within the scope ofthe claims appended hereto.

1. A method of treating a patient, said method comprising the steps of:passing a device including an expandable member in a collapsedconfiguration and a buoyancy member into the abdominal cavity of thepatient; and anchoring at least a portion of the expandable member,relative to at least one structure in the abdominal cavity.
 2. Themethod of claim 1, further comprising expanding the expandable member toan expanded configuration in a space in the abdominal cavity to performat least one of: prevention of expansion of the stomach of the patientinto the space; and compression of a portion of the stomach.
 3. Themethod of claim 1, wherein the buoyancy member and the expandable memberare passed into the abdominal cavity together, in the same method step.4. The method of claim 1, wherein the buoyancy member and the expandablemember are passed into the abdominal cavity in separate passing steps.5. The method of claim 1, wherein the steps are performed without directvisualization thereof.
 6. The method of claim 1, wherein at least one ofthe steps is performed under direct visualization.
 7. The method ofclaim 2, wherein the expandable member is expanded by inputting liquidtherein, and wherein the buoyancy member has a degree of positivebuoyancy, relative to the density of the surroundings of the device inthe abdominal cavity, to offset a negative buoyancy of the expandablemember containing the liquid, to provide a combined buoyancy of thedevice so that the device is substantially neutrally buoyant relative tothe surroundings.
 8. The method of claim 1, wherein the buoyancy memberis expandable, said method further comprising inputting gas into thebuoyancy member to expand the buoyancy member.
 9. The method of claim 2,wherein the buoyancy member is free floating with the expandable member.10. The method of claim 1, wherein the buoyancy member is fixed to aninner surface of the expandable member.
 11. The method of claim 8,further comprising adjusting buoyancy of the device by adjusting andegree of expansion of the buoyancy member by performing at least oneof: inputting additional gas into the buoyancy member, or removing gasfrom the buoyancy member.
 12. The method of claim 1, wherein thebuoyancy member is provided in the shape of an elongated spine.
 13. Themethod of claim 12, wherein the buoyancy member is fixed to an innersurface of the expandable member and rigidifies the expandable memberagainst kinking.
 14. The method of claim 1 comprising flattening orotherwise compressing the buoyancy member to a compressed configurationand maintaining the compressed configuration during said passing. 15.The method of claim 14, further comprising removing flattening orcompression force from the buoyancy member once the buoyancy member hasbeen placed in the abdominal cavity, wherein, upon removal of saidflattening or compression force, the buoyancy member self-expands to anon-compressed configuration.
 16. The method of claim 1, wherein saidpassing comprises passing the expandable member into the abdominalcavity prior to passing the buoyancy member into the abdominal cavity,and wherein the buoyancy member is passed into a chamber within theexpandable member when passed into the abdominal cavity.
 17. The methodof claim 1, wherein the device is passed through an opening in the skinof the patient, the opening through the skin being formed by an incisionno longer than about 7 cm.
 18. The method of claim 1, wherein the deviceis passed through an opening in the skin of the patient, the openingthrough the skin being formed by an incision no longer than about 5 cm.19. The method of claim 1, wherein said anchoring comprises anchoring atleast one attachment tab, extending from the expandable member, to theat least one structure.
 20. The method of claim 19, wherein saidanchoring comprises anchoring at least one of said attachment tabs to aninternal surface of the abdominal cavity.
 21. The method of claim 20,wherein said anchoring comprises passing at least one suture throughsaid at least one attachment tab and through the abdominal wall, andfixing said at least one suture externally of an external surface of theabdominal wall.
 22. The method of claim 20, wherein said anchoringcomprises passing at least one ribbon, attached to said at least oneattachment tab, through the abdominal wall, and fixing said at leastribbon externally of an external surface of the abdominal wall.
 23. Themethod of claim 1, further comprising repositioning the device in theabdominal cavity prior to said anchoring.
 24. The method of claim 23,wherein said repositioning comprises manipulating a positioning loopfrom outside the patient, the positioning loop being attached to thedevice.
 25. The method of claim 23, wherein said repositioning comprisespuncturing through a location of the skin of the patient and insertingan instrument into the abdominal cavity; capturing a positioning loopattached to the device; pulling a portion of the positioning loopthrough the abdominal wall; and applying tension to the positioning loopto move the device and draw a portion of the device up against aninternal surface of the abdominal wall.
 26. The method of claim 25,further comprising fixing a portion of the positioning loop externallyof the abdominal wall to prevent it from passing back into the abdominalcavity.
 27. The method of claim 23, wherein said repositioning comprisesgrasping at least one positioning tab mounted to said device, andperforming at least one of pushing, pulling or twisting forces on the atleast one positioning tab to reposition or reorient the device.
 28. Themethod of claim 20, wherein said anchoring comprises passing at leastone Q-ring through said at least one attachment tab and through theabdominal wall, thereby fixing said at least one attachment tab to theabdominal wall.
 29. The method of claim 19, wherein said anchoringcomprises passing at least one Q-ring through said at least oneattachment tab and through the at least one structure, thereby fixingsaid at least one attachment tab to the at least one structure.
 30. Themethod of claim 21, wherein said anchoring comprises puncturing througha location of the skin above a location of at least one said suture andinserting an instrument into the abdominal cavity; capturing the suture;and wherein said passing at least one suture through the abdominal wallcomprises pulling a portion of the at least one suture through theabdominal wall; applying tension to the at least one suture to draw theat least one attachment tab against an internal surface of the abdominalwall; and fixing the at least one suture externally of the abdominalwall. 31-171. (canceled)